jquery with existing app

jquery with existing app

hi there,
I've been asked to add several features to an existing app (in php) that is used by photographers to upload and display photos.
in stand-alone test code I've build a couple of forms and grids using
plug-ins that work well.

when the form is loaded the options are defined, including the pre- and post- submit callbacks.
I've put the form into the app's source code, but pressing the submit button causes only the pre-submit callback to fire not the post-.

with the grid, there's a url option that specifies the php file whence comes the data that will populate the grid. when the grid is in the app's source code this file is never called.

I've run extensive tests and the code is correct, database access is correct, etc.
the reasons for these files not being called probably lie in how the app's ajax has been set up.

I was wondering if anyone else had encountered similar problems.
I can work around the form problem ok but I'm looking at being forced to code the grids manually from scratch. yikes!

any ideas would be greatly appreciated.
Brian