That program should work, but needs modifying first. Unless you are comfortable with ABAP lets ignore that option.
If you are on 4.7 or lower then you can very easily record a CATT script (tx SCAT) to delete them. If you are on ECC5/6 then use transaction SECATT to do this. Google (or SDN search ) for SECATT tutorials which will tell you how to use the tool. Follow the examples and learn how to parameterise a field and you will easily be able to create a script to perform the deletions.
Another option is to use LSMW to do the same which I know is a popular tool with some posters on here.
