IE has lost its File Associations

I have Windows ME and IE 5.5. When I click on a link on a web page connecting me to a Realplayer .RM or .RAM file instead of launching Realplayer the only option I get is to save the .RM file to disk. The option to “open from current location” is greyed out.
If I then save the file to disk and then double click on it within Windows Explorer it launches in Realplayer straight away.
Within Windows Explorer I’ve checked the file associations and they’re related fine to Realplayer in there, its only from within IE that it doesn’t seem to know what kind of files these are and only gives me the option to save them to disk.
Any ideas?