I just encountered the same problem.
I don't think its to hard to write somekind of subroutine for it. It disturbs me enough that I might go to a 16 bit microcontroller. The origin of the problem may be in that the 8051 is a communication oriented microprosser.
Try doing decimal divition by hand for decimal. Also, the fact that when a binary number is divided by two its equivelent to shifting down. 110/10=11
etc. 11100/100=111. Something for HEX?
111000/F=111?
1100/(F+2)=A(1100/F)+B(1100/2), thats a theorom. No reason that it is neccerally true, but it is!