I've got the same problem as this on Ubuntu 12.04 LTS
I did some tracing of the crash and it's occurring in on_drag_motion()
It appears that calls to targets_include_text / targets_include_uri at the start of the function are somehow bugged. Occasionally after the calls to them accessing self will cause a segfault.
No idea where to look further for the root cause of this - could be in some bindings?
For my own happiness - I've been able to remove the initial if / return statement containing these this function calls - the result is that when you drag a file / test into terminals the highlighting for a window split shows up - but no crash - I can live with that.
Hope this serves as a pointer to some one who can dig deeper and fix this.