How about:

my @sorted_keys = sort { $hash{$a}->{oid} cmp $hash{$b}->{oid} } keys 
+%hash;
[download]

which will sort with string comparison because of the use of cmp use <=> if you want numerical comparison, but note that the 'oid' field has a non-numerical value.

-- 
#!/usr/bin/perl -w
use strict;$;=
";Jtunsitr pa;ngo;t1h\$e;r. )p.e(r;ls ;h;a;c.k^e;rs 
";$_=$;;do{$..=chop}while(chop);$_=$;;eval$.;
[download]