You could just parse it with HTML::Parser, which will downconvert it for you.

Or, use HTML::Entities, it'd be something like:

use HTML::Entities;
$_ = 'http://www.dns&
+#16;magicsite.net&10
+85287724@1085287723&1063256813@3493727992?75541114&proxy=1063
+256794?1085287723@1063256813?www.su2537.tw|www.&
+#16;.hk?/proxy
+=1063256803@2204624165:2030@2204624133?/@1085307406:8080@1085305176@%
+31%30%38%35%33%30%35%31%36%35';
print decode_entities $_;
[download]

Hmm. They have illegal characters in their DNS name. How sick.

-- Randal L. Schwartz, Perl hacker