Hung requests with SPIP 2.0.5

Hi all,

We've encountered a problem with a client's site based on SPIP 2.0.5.  
Sometimes a request for a public page will hang. I've never seen the  
problem, but others here have. We can solve the problem by deleting  
everything in /tmp/ via FTP and reloading the page.

Apparently, SPIP encounters a deadlock of some description while  
regenerating a page. I assume that this has something to do with lock  
being acquired and not released properly (perhaps after  
max_execution_time?).

We can't seem to upgrade the site to SPIP 2.0.8 because the upgrade  
procedure complains about the database schema. We've used Champs  
Extras 2 to add columns to spip_articles. Could this be the cause of  
the "can't upgrade" problem?

If this is a known problem which is resolved in a later version, then  
I'll do the work to upgrade the site. If it's not a known problem,  
can anyone provide any suggestions about finding the cause and fixing  
it? At the moment, I'm not even sure what it *is* so it's rather hard  
to know where to start. 

Thanks,

Thomas Sutton

Web Developer
bouncingorange
graphic + web design