Bug #1921: NoMethodError: undefined method `try_activate' for Gem:Module when starting vim after install of command-t

I get a

NoMethodError: undefined method `try_activate' for Gem:Module

when starting vim after installing command-t on Mac OS X 10.7.2.

MacVim is installed via homebrew and linked against a ruby 1.9.2-p290 that I have installed with rbenv and ruby-build. As far as I can see the same version of ruby is used by MacVim and command-t -- there is no reference to the system ruby. Command-T is installed as a submodule directly from github so it should be the latest code. I'm using mvim -v (console version) but I can't imagine that makes any difference...

Errors/versions below:

== Vim error:
Error detected while processing ~/.vim/bundle/command-t/plugin/command-t.vim:
line  164:
NoMethodError: undefined method `try_activate' for Gem:Module
Press ENTER or type command to continue

== Output from building command-t:
rake make
/Users/rohrer/.rbenv/versions/1.9.2-p290/bin/ruby extconf.rb
checking for ruby.h... yes
creating Makefile
gcc -I. -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/x86_64-darwin11.2.0 -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/ruby/backward -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1 -I. -DHAVE_RUBY_H -I'/Users/rohrer/.rbenv/versions/1.9.2-p290/include'  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -fno-common -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long  -pipe  -std=c99 -Wall -Wextra -Wno-unused-parameter -o ext.o -c ext.c
gcc -I. -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/x86_64-darwin11.2.0 -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/ruby/backward -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1 -I. -DHAVE_RUBY_H -I'/Users/rohrer/.rbenv/versions/1.9.2-p290/include'  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -fno-common -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long  -pipe  -std=c99 -Wall -Wextra -Wno-unused-parameter -o match.o -c match.c
gcc -I. -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/x86_64-darwin11.2.0 -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/ruby/backward -I/Users/rohrer/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1 -I. -DHAVE_RUBY_H -I'/Users/rohrer/.rbenv/versions/1.9.2-p290/include'  -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE   -fno-common -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long  -pipe  -std=c99 -Wall -Wextra -Wno-unused-parameter -o matcher.o -c matcher.c
gcc -dynamic -bundle -o ext.bundle ext.o match.o matcher.o -L. -L/Users/rohrer/.rbenv/versions/1.9.2-p290/lib -L. -L'/Users/rohrer/.rbenv/versions/1.9.2-p290/lib'  -Wl,-undefined,dynamic_lookup -Wl,-multiply_defined,suppress -Wl,-flat_namespace  -lpthread -ldl -lobjc

$ ruby --version
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-darwin11.2.0]

$ gem --version
1.8.11

$ vim --version
VIM - Vi IMproved 7.3 (2010 Aug 15, compiled Sep 28 2011 15:32:08)
MacOS X (unix) version
Included patches: 1-315
Compiled by rohrer@mycroft.local
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 +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 -isysroot /Developer/SDKs/MacOSX10.7.sdk -mmacosx-version-min=10.7 -arch x86_64 -D_FORTIFY_SOURCE=1     -I/System/Library/Frameworks/Tcl.framework/Headers  -D_REENTRANT=1  -D_THREAD_SAFE=1  -D_DARWIN_C_SOURCE=1  
Linking: gcc   -L. -L/Users/rohrer/.rbenv/versions/1.9.2-p290/lib  -L. -L/Users/rohrer/.rbenv/versions/1.9.2-p290/lib       -Wl,-syslibroot,/Developer/SDKs/MacOSX10.7.sdk -mmacosx-version-min=10.7 -arch x86_64 -L/usr/local/lib -o Vim -framework Cocoa -framework Carbon      -lncurses -liconv -framework Cocoa    -fstack-protector -L/usr/local/lib  -L/System/Library/Perl/5.12/darwin-thread-multi-2level/CORE -lperl -lm -lutil -lc -framework Python  -F/System/Library/Frameworks -framework Tcl -framework CoreFoundation -lruby-static -lobjc -L/Users/rohrer/.rbenv/versions/1.9.2-p290/lib