Compare and find records of file1 not in file2

hi.. i am using solaris system and ksh and using nawk to get records of file1 not in file2(not line by line comparison). code i am using is

nawk 'NR==FNR{a[$0]++} !a[$0] {print"line:" FNR"->" $0} ' file2 file1

same command with awk runs perfectly on darwin kernel(mac) but in solaris it does line by line comparison. please suggest as this is v imp to me.

Show the input you have, the output you want, and the output you're getting please.

NR==FNR{a[$0]++;next}