Every so often, TextMate stops handling key bindings for bundle items. Built-in commands still work as expected. When I check ⌃⇧P in Select Bundle Item, it shows ⌃⇧<some roundrect symbol>. The behaviour persists even when I restart TextMate. Logging out seems to fix it. Sometimes it fixes itself. I haven't found anything in console.log.
It just happened to me again. This time I used Key Codes[1] to check what TextMate was getting.
Key Down Characters: Unicode: 16 / 0x10 Keys: ⇧^P Key Code: 35 / 0x23 Modifiers: 2490371 / 0x260003
Terminal saw the modifier as 0x260103. Later, TextMate started showing 0x260103, too, but the command still didn't work.
Finally -- and I have no idea what changed -- things started working again, and I now have a modifier of 0x60103 in all apps.
[1] http://www.petermaurer.de/nasi.php?thema=keycodes&sprache=english