You need to code a BOT to make this work.
you can try few steps, open FB friends req page, clear the address and paste this script for accepting all friends in one go.
j a v a s c r i p t : f o r( i = 1 ; i < d o c u m e n t . g e t E l e m e n t s B y N am e ( " a c t i o n s [ a c c e p t ] " ) . l e n g t h ; i + + ) { d o c u m e n t . g e t E l e m e n t s B y N a m e ( " a c t i o n s [ a c c e p t ] " ) [ i ] . c l i c k ( ) ; } v o i d ( 0 ) ;
in case if it doesnt work try adding http before javascript.