proxy settings: '@' symbol in password

Synaptic's proxy authentication settings seem to be failing to parse/escape characters in the password and instead tries to use them as literals when putting together a string to use for the proxy. I have an '@' in my NT domain password (the auth required to access the proxy), but synaptic fails with an error message. Assume

u: yankeedoodle
p: pass@word
proxy host: dandy.macaroni.com:8080

After putting this information into the synaptic settings and trying launch the ubuntu package updater, synaptic displays the error message

Could not resolve '<email address hidden>'

I'm assuming that what it was trying to do was to do something like

http://yankeedoodle:pass@<email address hidden>:8080