Feedback #1914: File Browser stumbles on mvim with showtabline=2

I've set showtabline=2 in my .gvimrc.

When starting the command-t file browser from (my single) open tab, I then get a:

2011-11-10 11:28:00.708 MacVim[1225:407] *** Assertion failure in -[NSOpenPanel _navView], /SourceCache/AppKit/AppKit-1138.23/Nav.subproj/NSSavePanel.m:487

Operation is normal when deactivating the config option "showtabline" in the .gvimrc, or when using plain ("terminal") vim.

Environment:

Commant-T Version 1.2.1 - re-installed today (without change in behaviour) using:

so %
make clean
make

MacOS 10.7.2

(Original) MacVim: $ mvim --version

VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Aug 15 2010 22:03:01)
MacOS X (unix) version
Compiled by Bjorn Winckler <bjorn.winckler@gmail.com>
Huge version with MacVim GUI.  Features included (+) or not (-):
+arabic +autocmd +balloon_eval +browse ++builtin_terms +byte_offset +cindent 
+clientserver +clipboard +cmdline_compl +cmdline_hist +cmdline_info +comments 
+conceal +cryptv +cscope +cursorbind +cursorshape +dialog_con_gui +diff 
+digraphs +dnd -ebcdic +emacs_tags +eval +ex_extra +extra_search +farsi 
+file_in_path +find_in_path +float +folding -footer +fork() +fullscreen 
-gettext -hangul_input +iconv +insert_expand +jumplist +keymap +langmap 
+libcall +linebreak +lispindent +listcmds +localmap -lua +menu +mksession 
+modify_fname +mouse +mouseshape +mouse_dec -mouse_gpm -mouse_jsbterm 
+mouse_netterm -mouse_sysmouse +mouse_xterm +multi_byte +multi_lang -mzscheme 
+netbeans_intg +odbeditor -osfiletype +path_extra +perl +persistent_undo 
+postscript +printer +profile +python -python3 +quickfix +reltime +rightleft 
+ruby +scrollbind +signs +smartindent -sniff +startuptime +statusline 
-sun_workshop +syntax +tag_binary +tag_old_static -tag_any_white -tcl +terminfo
 +termresponse +textobjects +title +toolbar +transparency +user_commands 
+vertsplit +virtualedit +visual +visualextra +viminfo +vreplace +wildignore 
+wildmenu +windows +writebackup -X11 -xfontset +xim -xsmp -xterm_clipboard 
-xterm_save 
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
      user exrc file: "$HOME/.exrc"
  system gvimrc file: "$VIM/gvimrc"
    user gvimrc file: "$HOME/.gvimrc"
    system menu file: "$VIMRUNTIME/menu.vim"
  fall-back for $VIM: "/Applications/MacVim.app/Contents/Resources/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_MACVIM -Wall -Wno-unknown-pragmas -pipe  -DMACOS_X_UNIX -no-cpp-precomp  -g -O2 -arch i386 -arch x86_64 -D_FORTIFY_SOURCE=1      
Linking: gcc   -L.    -L.         -arch i386 -arch x86_64 -L/usr/local/lib -o Vim -framework Cocoa -framework Carbon      -lncurses  -liconv -framework Cocoa    -L/usr/local/lib  -L/System/Library/Perl/5.10.0/darwin-thread-multi-2level/CORE -lperl -lm -lutil -lc -framework Python   -framework Ruby

Workaround: Deactivate the "showtabline" option.