You need to install a different bluetooth stack for your ipad (that allows data transfer).
There are a couple out there (one is ibluever and the other is mywi ondemand)... there may be more but those are the 2 I know of.
Now, I am unable to jailbreak my ipad2 (since it came with 4.3.5) so I have not tried them out yet... but either of those 2 programs through cydia should work for bluetooth tether.
Then, just run pdanet 3.02 on your samsung infuse ... choose bluetooth tether then on your jailbroken ipad set up which over program you decided to use and tether them together
D.