Perl 5.8.0
timethis 1000: 48 wallclock secs (46.76 usr +  0.02 sys = 46.78 CPU) @ 21.38/s (n=1000) 

Perl 5.6.1
timethis 1000:  1 wallclock secs ( 0.70 usr +  0.00 sys =  0.70 CPU) @ 1428.57/s (n=1000)