Logged In: YES 
user_id=6656

Argh.  Don't know how the bounds check typo crept in; I'm
sure that was right in earlier incarnations of the patch. 
Easy to fix, though.

Wrt the exceptions list: yes, I too would like a better
solution.  There are situations where execution jumps into
the middle of a line; for loops for one (maybe the only
one).  Look at the output of dis.py (either before or after
this patch).

Currently, the line beginning a for loop gets two "co_lnotab
blocks" (if that makes sense) which could be used to get
this right; we only call the trace function if the current
offset exactly matches a byte increment in co_lnotab. 
That's spectacularly subtle, though.

I'm afriad the last comment doesn't make any sense to me. 
Can you elaborate?  What's in spam.py?