We just discovered today that in fact the validate plugin is not compatible with jquery 1.4.2. In particular it overwrites the new 1.4.2 delegate() function with it's own version with a different order of parameters than the one in jquery core ( and apparently differently functioning as well, though we didn't research that part too much). At first we tried just removing the one in the validate function and rewriting the two places that use it to use the core version. We ended up having problems when we tried to do that though, so we ended up just renaming the validation delegate function to something like val_delegate() and changing validation's internal references to it to point to the renamed one. That fixed all of our problems.
