Many of us unfortunately. The cause is flexing of the full/empty tank and the rigid drain piping. The drain piping acts like a lever and cracks the spud, or area around it.
The fix is possible, and not bad of a job. I will see if I can find my fix-it-slideshow.
Drain the tank a while before the fix.
Here is the link:
https://picasaweb.google.com/Jimsue1...eat=directlink
Any questions, just ask. Good luck with it.