Recently I’d started work on a new project in APEX 4.1 and a target browser of IE6. As part of the initial project setup I used the APEX Form Validation plugin provided by Guido Zeelen which is based on the jQuery validation plugin developed by Jörn Zaefferer from bassistance.de. Whilst I had no issue with the plugin in 4.0.x and IE6, I ran into a problem in APEX 4.1 which meant that on page submit all forms were passing as valid in IE6,7,8 even when they were invalid. However on Firefox, Chrome it was working perfectly… go figure!
There were a couple of red herrings that came up when I was looking for a solution, but in the end it was due to APEX running jQuery 1.6.2 and using v1.7 of the jQuery validation plugin which wasn’t a supported combination. The simple fix was to upgrade to v1.9.0 and I’m happy to say that it’s now working again on IE6,7,8…. well not entirely happy after losing a number of hours debugging, but hopefully you won’t if you run into the same problem