Not sure why you're getting different results, but I can tell you hoe to adjust what gets escaped. &uri_escape can take a second argument, a string which specifies a character class to escape. "^A-Za-z" will escape everything but ASCII alphabetics.

From the command line mine does ( with versions):

$ perl -MURI::Escape -MHTTP::Request -e'my $ru=uri_escape("http://foo.
+org/cgi-bin/bar.cgi?baz = qu ux;foo=dim");$v=new HTTP::Request(url=>"
+http://foo.org/cgi-bin/bar.cgi?ru=$ru");print $v->url,$/,"URI::Escape
+ v",$URI::Escape::VERSION,$/,"Perl v",$],$/'
http://foo.org/cgi-bin/bar.cgi?ru=http%3A%2F%2Ffoo.org%2Fcgi-bin%2Fbar
+.cgi%3Fbaz%20%3D%20qu%20ux%3Bfoo%3Ddim
URI::Escape v3.20
Perl v5.006001
$
[download]

on Linux. I wonder if the difference is in defaults selected at build?

After Compline,
Zaxo