Problem with Replace statement?

Hi Guys,

I am using Replace statement for replacing '%20' in a partucular field like given below

" Replace All occurrences of REGEX '%20' in I_ZSTR_BPSITEUSER-FIRSTNAME with space ."

But the problem is if Firstname = " Gopi%20%20%20A " after using this replace i am getting as

" GopiA " but what my req is i need like "Gopi A"(i want spaces in %20 place)so how to get it?

Thanks,

Gopi