Trimming internal table based on criteria

Dear ABAP gurus,

I have an internal table say itab1 which has 2 fields- user,terminal( 'terminal' field denotes terminal from which 'user' has logged in)

This internal table has records.

From this table I want a list of all those users who have logged in from more than 1 terminal

How can I get the required list in another internal table (say itab2) ?

(itab2 will have the same 2 fields,so required list is basically a subset of itab1)

NOTE- Think of this as -  itab1 has 2 fields f1,f2...for each f1 there are greater than or equal to values of f2....I want only

those f1 which have more than one f2 in itab2 having same type as itab1.

Thanks,