diff --git a/autoload/vundle/compat.vim b/autoload/vundle/compat.vim
new file mode 100644
index 0000000..ea9b69a
--- /dev/null
+++ b/autoload/vundle/compat.vim
@@ -0,0 +1,155 @@
+" vundle - vim compatibility support module
+
+" this abstracts the operation:
+"  exec 'set runtimepath-='.vundle#compat#fnameescape(LIST)
+"
+" notes:
+"  * it attempts to do the "real thing", if it can;
+"   * otherwise, it has a number of fallback scenarios, ordered by
+"      reliability;
+"  * special case: if a:dirs contains a ',' (multiple entries), this function
+"     attempts the
+"      exec 'set runtimepath-='.vundle#compat#fnameescape(LIST)
+"     first.
+"     if that does not alter &runtimepath, then it tries to remove a:dirs
+"     elements individually;
+"
+" args:
+"  dirs [string]: described as 'LIST' above;
+"
+" for now, it does not produce an explicit return value
+"
+func! vundle#compat#rtp_rm_entry(dirs)
+  " debug: echomsg '[debug] vundle#compat#rtp_rm_entry(): entered. rtp: ' . string(&rtp) . '; dirs: ' . string(a:dirs)
+  " optimisation: there seems to be a few of these cases
+  if empty(a:dirs)
+    return 0
+  endif
+  let l:runtimepath_orig = &rtp
+  let l:processed_flag = 0
+  let l:elem_separator = ','
+  for l:process_stage in range(1, 4)
+    if ( l:process_stage == 1 )
+      exec 'set rtp-='.vundle#compat#fnameescape(a:dirs)
+      " if &rtp was altered, or a:dirs had only one element, we won't keep
+      "  trying
+      let l:processed_flag = ( ( &rtp != l:runtimepath_orig ) || ( stridx(a:dirs, l:elem_separator) < 0 ) )
+    elseif ( l:process_stage == 2 )
+      if exists('*split') && exists('*filter') && exists('*join')
+        " a bit costly, but more compatible
+        let l:runtimepath_list = split(&rtp, l:elem_separator, 1)
+
+        for l:entry_dir in split(a:dirs, l:elem_separator, 1)
+          let l:runtimepath_list = filter(l:runtimepath_list, 'v:val != l:entry_dir')
+        endfor
+        " assemble the runtime variable from the list
+        let &rtp = join(l:runtimepath_list, l:elem_separator)
+        let l:processed_flag = 1
+      endif
+    elseif ( l:process_stage == 3 )
+      if exists('*escape')
+        " from fnameescape() documentation:
+        "  it escapes: " \t\n*?[{`$\\%#'\"|!<"
+        "  plus, depending on 'isfname', other characters.
+        "  (TODO: add those cases, if needed)
+        exec 'set rtp-='.escape(a:dirs, " \t\n*?[{`$\\%#'\"|!<")
+        let l:processed_flag = 1
+      endif
+    elseif ( l:process_stage == 4 )
+      " cheap and cheerful (but no escaping)
+      exec 'set rtp-='.a:dirs
+      let l:processed_flag = 1
+    endif
+    if l:processed_flag
+      break
+    endif
+  endfor
+  " debug: echomsg '[debug] vundle#compat#rtp_rm_entry(): exiting. rtp: ' . string(&rtp)
+endf
+
+" abstracts the following operations:
+"  exec 'set runtimepath^='.vundle#compat#fnameescape(LIST)
+"  exec 'set runtimepath+='.vundle#compat#fnameescape(LIST)
+"  exec 'set runtimepath='.vundle#compat#fnameescape(LIST)
+"
+" args:
+"  dirs [string]: described as 'LIST' above;
+"  addset_operator [string]: one of:
+"   '^': prepend ('set runtimepath^=');
+"   '+': append ('set runtimepath+=');
+"   '':  set ('set runtimepath=');
+"
+" for now, it does not produce an explicit return value
+"
+func! vundle#compat#rtp_addset_entry(dirs, addset_operator)
+  " debug: echomsg '[debug] vundle#compat#rtp_addset_entry(): entered. rtp: ' . string(&rtp) . '; dirs: ' . string(a:dirs) . '; operator: ' . string( a:addset_operator )
+  if exists('*fnameescape')
+    exec 'set rtp'.a:addset_operator.'='.fnameescape(a:dirs)
+  else
+    " a bit costly, but more compatible
+
+    if ( a:addset_operator == '' ) && empty(&rtp)
+      " this should be quick
+      let &rtp = a:dirs
+    else
+      let l:elem_separator = ','
+
+      " only add the elements not already present in &runtimepath
+      if exists('*split') && exists('*filter') && exists('*join')
+        " a bit costly, but more compatible
+        let l:dirs_list = split(a:dirs, l:elem_separator, 1)
+        for l:entry_dir in split(&rtp, l:elem_separator, 1)
+          let l:dirs_list = filter(l:dirs_list, 'v:val != l:entry_dir')
+        endfor
+        let l:dirs = join(l:dirs_list, l:elem_separator)
+      else
+        " nothing we can do about this: we'll take the input as is
+        let l:dirs = a:dirs
+      endif
+
+      if !empty(l:dirs)
+        if a:addset_operator == '^'
+          let &rtp = l:dirs . l:elem_separator . &rtp
+        elseif a:addset_operator == '+'
+          let &rtp = &rtp . l:elem_separator . l:dirs
+        else
+          " FIXME: report internal error
+        endif
+      endif
+    endif
+  endif
+  " debug: echomsg '[debug] vundle#compat#rtp_addset_entry(): exiting. rtp: ' . string(&rtp)
+endf
+
+func! vundle#compat#has_dos_windows_paths()
+  return exists('+shellslash')
+endf
+
+" provides the same functionality as shellescape()
+"  (even on vim versions that don't support it)
+"
+" note: behaviour taken from vim-7.1 documentation
+func! vundle#compat#shellescape(string_value)
+  if vundle#compat#has_dos_windows_paths()
+    if &shellslash
+      " return as is?
+      return a:string_value
+    else
+      " double all double quotes within string,
+      "  and enclose result in double quotes
+      return '"' . substitute(a:string_value,'"','""','g') . '"'
+    endif
+  else
+    " replace all "'" with "'\''"
+    return "'" . substitute(a:string_value,"'","'".'\\'."''",'g') . "'"
+  endif
+endf
+
+"  (first appeared in a major release in vim-7.2)
+let s:vundle_compat_has_fnameescape = exists( '*fnameescape' )
+function vundle#compat#fnameescape( fname )
+  " from documentation: it escapes: " \t\n*?[{`$\\%#'\"|!<"
+  "  plus, depending on 'isfname', other characters.
+  return ( s:vundle_compat_has_fnameescape ? fnameescape( a:fname ) : escape( a:fname, " \t\n*?[{`$\\%#'\"|!<" ) )
+endfunction
+
diff --git a/autoload/vundle/config.vim b/autoload/vundle/config.vim
index c665d4d..173e97b 100644
--- a/autoload/vundle/config.vim
+++ b/autoload/vundle/config.vim
@@ -172,7 +172,7 @@ func! s:rtp_add_defaults()
   let &rtp = current
   let default_rtp_items = split(default, ',')
   if !empty(default_rtp_items)
-    let first_item = fnameescape(default_rtp_items[0])
+    let first_item = vundle#compat#fnameescape(default_rtp_items[0])
     exec 'set rtp-=' . first_item
     exec 'set rtp^=' . first_item
   endif
@@ -185,10 +185,12 @@ endf
 " ---------------------------------------------------------------------------
 func! s:rtp_rm_a()
   let paths = map(copy(g:vundle#bundles), 'v:val.rtpath')
-  let prepends = join(paths, ',')
-  let appends = join(paths, '/after,').'/after'
-  exec 'set rtp-='.fnameescape(prepends)
-  exec 'set rtp-='.fnameescape(appends)
+  if !empty(paths)
+    let prepends = join(paths, ',')
+    let appends = join(paths, '/after,').'/after'
+    call vundle#compat#rtp_rm_entry(prepends)
+    call vundle#compat#rtp_rm_entry(appends)
+  endif
 endf
 
 
@@ -198,10 +200,12 @@ endf
 " ---------------------------------------------------------------------------
 func! s:rtp_add_a()
   let paths = map(copy(g:vundle#bundles), 'v:val.rtpath')
-  let prepends = join(paths, ',')
-  let appends = join(paths, '/after,').'/after'
-  exec 'set rtp^='.fnameescape(prepends)
-  exec 'set rtp+='.fnameescape(appends)
+  if !empty(paths)
+    let prepends = join(paths, ',')
+    let appends = join(paths, '/after,').'/after'
+    call vundle#compat#rtp_addset_entry(prepends,'^')
+    call vundle#compat#rtp_addset_entry(appends,'+')
+  endif
 endf
 
 
@@ -212,8 +216,10 @@ endf
 "           'after' directory will also be removed.
 " ---------------------------------------------------------------------------
 func! s:rtp_rm(dir) abort
-  exec 'set rtp-='.fnameescape(expand(a:dir, 1))
-  exec 'set rtp-='.fnameescape(expand(a:dir.'/after', 1))
+  if !empty(a:dir)
+    call vundle#compat#rtp_rm_entry(expand(a:dir, 1))
+    call vundle#compat#rtp_rm_entry(expand(a:dir.'/after', 1))
+  endif
 endf
 
 
@@ -224,8 +230,10 @@ endf
 "           'after' directory will also be added.
 " ---------------------------------------------------------------------------
 func! s:rtp_add(dir) abort
-  exec 'set rtp^='.fnameescape(expand(a:dir, 1))
-  exec 'set rtp+='.fnameescape(expand(a:dir.'/after', 1))
+  if !empty(a:dir)
+    call vundle#compat#rtp_addset_entry(expand(a:dir, 1), '^')
+    call vundle#compat#rtp_addset_entry(expand(a:dir.'/after', 1), '+')
+  endif
 endf
 
 
diff --git a/autoload/vundle/installer.vim b/autoload/vundle/installer.vim
index e05cff2..7859807 100644
--- a/autoload/vundle/installer.vim
+++ b/autoload/vundle/installer.vim
@@ -482,7 +482,7 @@ func! vundle#installer#shellesc(cmd) abort
   if ((has('win32') || has('win64')) && empty(matchstr(&shell, 'sh')))
     return '"' . substitute(a:cmd, '"', '\\"', 'g') . '"'
   endif
-  return shellescape(a:cmd)
+  return vundle#compat#shellescape(a:cmd)
 endf
 
 
diff --git a/test/vimrc b/test/vimrc
index d8455a7..984d4c7 100644
--- a/test/vimrc
+++ b/test/vimrc
@@ -9,6 +9,9 @@ let bundle_dir = '/tmp/vundle-test/bundles/'
 " Vundle Options
 " let g:vundle_default_git_proto = 'git'
 
+" NOTE: the 'autoload' modules are not available. if they were,
+"  we could escape the 'bundle_dir' like this:
+"  vundle#compat#shellescape(bundle_dir)
 silent execute '!mkdir -p '.bundle_dir
 silent execute '!ln -f -s ~/.vim/bundle/Vundle.vim '.bundle_dir