I wish to add a link on my node (cck with 1 "File" field) in order to be able to click on the link to download the file attachment with a custom protocol in the form of customprotocol://, similar to mailto://, ssh:// etc...

I have looked at the custom links module but have 2 problems - maybe I need something else than custom links?

- in the available tokens of custom url I don't have the choice to select my cck file attachment, only node id, title, etc... How can I add this token? is there an admin module to define tokens without PHP, with wildcards and access to cck fields

- in the custom links "Path" field if I define something else than http://, the ":"caracter is percent escaped with %3A:
example:
http://mysite.com/q=customprotocol%3A//mysite.com/share/sites/default/fi...

In the end I would like to create a link similar to
customprotocol://mysite.com/share/sites/default/files/[myfile.ext]
where [myfile.ext] is the name of the file attached in the cck field of type "File" of my node

Thank you!