Yes, I can confirm the access violation on 0.9.28.2 on Intel Mac, but it doesn't occur on PowerPC Mac. Also, appears to be fixed in 0.9.29 SVN. If you really need this control (I've never used it for anything), you could try a 0.9.29 snapshot or build from SVN:
http://www.lazarus.freepascal.org/index.php/topic,8140.msg39177.html#msg39177
Thanks.
-Phil
Phil,
Tried the .9.29, and synedit still gives access violation on an intel mcbkpro osx 10.4.11.
But it laz installed without a recompile anyway... I'll go do a bug report.