Hello!
>  >    sort="attr1/cmp1,attr2,attr3/cmp3/desc,...."
   I tested the patch with Zope, and it works perfectly.
   I put the patch and test suite into Collector:
http://classic.zope.org:8080/Collector/2120/view
Oleg.
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     Oleg Broytmann     http://www.zope.org/Members/phd/     phd@phd.pp.ru
           Programmers don't die, they just GOSUB without RETURN.