Bug make_url does nothing with a "?"

[TQuilla]

r27100
Trying to make a URL for item "drippy plum(?)" results in no URL encoding for the "?"

string url = make_url("https://kol.coldfront.net/thekolwiki/index.php/" + $item[drippy plum(?)].replace_string(" ", "_"), false, false);
print(url);
visit_url(url);

This seems to work:
string url = make_url("https://kol.coldfront.net/thekolwiki/index.php/" + $item[drippy plum(?)].replace_string(" ", "_").replace_string("?", "%3F"), false, false);
print(url);
visit_url(url);

TQuilla/sacha