This is strange. It works without ANY line of code!
I just created simple project and it wraps text out of the box.
I mean I didn't wrote a single line of code I just clicked couple times in designer and filled table with data (I didn't change ANY property).
See this project tableTextWrapTest.zip when you manually extend line text is nicely warped. Tested on Linux Qt 4.8.
Maybe you should specify more precisely what is your problem.
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