I've been having similar, but more severe issues related to the GDB debugger for the up-coming 0.9.30 release of Lazarus.
It would seem that the 0.9.29 (Date: 2011-01-02 SVN Revision: 28855) version of Lazarus will give out a Debugger crashing error from any of my saved projects. I don't use an NTFS partition, instead I only use the same drive that Snow Leopard is installed to. Half of the time however when I click on the Run button, it'll actually run the program, while the other half I only get the error. The program always compiles successfully.
I have just found out a way NOT to get the error. If your last open project was deleted after Lazarus was closed and you open Lazarus, it'll create a non-saved default program that is open and can be compiled. When I hit the 'Run' button then I DON'T get a debugger error.
By this, I'm lead to believe that somehow GDB is also disturbed not only by NTFS, but by Mac's own file system as well.
My system's specs are as follows:
Intel iMac running Mac OS X 10.6.6
4 GB RAM with 1 TB solid state hard drive
Latest Apple's Developer SDK (Xcode version 3.2.5 1760)
The version of Lazarus & FPC is:
Lazarus version 0.9.29
Date: 2011-01-02
SVN Revision: 28855
i386-darwin-carbon
FPC Version 2.4.2