Creating custom infotype.

Hi experts,

Good day i am creating custom info-type from abap program by using HR_INFOTYPE_OPERATION, Program is terminating at line num 270 :

"ASSIGN record TO <record> CASTING TYPE (tabname). "XDP UniCode"

over here tabname value is like P9999 but actual table is PA9999

The very first statement of this FM is :

DATA TABNAME  LIKE DNTAB-TABNAME VALUE 'P'.

so how can i change the vlaue from P to PA.

Thanks in advance,

Hafiz.