await start weirdness in Perl 6

gistfile1.txt

05:20:34 ~/temp $ time perl6 -MHTTP::UserAgent -e 'my $url = "http://www.rakudo.org/"; my $ua = HTTP::UserAgent.new; $ua.get($url)'

real	0m12.382s
user	0m10.374s
sys	0m0.203s
05:21:33 ~/temp $ time perl6 -MHTTP::UserAgent -e 'my $url = "http://www.rakudo.org/"; my $ua = HTTP::UserAgent.new; $ua.get($url); await start { $ua.get($url) }'

real	0m13.869s
user	0m10.607s
sys	0m0.215s
05:21:59 ~/temp $ time perl6 -MHTTP::UserAgent -e 'my $url = "http://www.rakudo.org/"; my $ua = HTTP::UserAgent.new; await start { $ua.get($url) }'

# hangs forever unless we do a FIRST $ua.get outside of start {}