Crash when trying to ride minecarts

I cant ride in minecarts. the attached file is the latest crash. if you want i can put in all of the crashes on a seperate page

when i tried to even move a minecart without me in it it still crashed

Crash... this has been happening since 1.4.4

to make this crash all i did was put down a trail and put the minecart and touch it. it instantly crashes after that