An alternative to jmp @a+dptr, especially if you need the dptr already for something else, or if you need a bigger range than jmp @a+dptr is capable of is to calculate the address where you want to go, push it on the stack and then execute a RET instruction. This will also get you where you want to go.

Example:

		add	a,low(base_addr)	;Calculate low order address
		push	acc			;put it on the stack
		mov	a,high(base_addr)	;Calculate high order address
		push	acc			;Both bytes on the stack now
		ret				;Pop them and put them in the PC