Right here:
in functions.php, find:
$displayname = substr($entry, 0, 44);
You can just modify the number 44 to suit ur needs..
EDIT:
You might also change this:
if(strlen($entry) >= 47)
Change the 47 to whatever number of chars it should start truncating on.
Ok Cool!

But that is still hardcoding the stringlength.
Is it any way to make the length dependent on the size of the coloumn?
Something like
if(strlen($entry) >= sizeof(coloumn[max]))
I do not know if that is possible with php and the way TF is coded, but that would be really neat!!

Hardcoding the string will work for now
Thanks!!