tags with spaces in it issue - acts_as_tagged_on_steriods

I am using acts_as_tagged_on_steriods for tagging which works well for
single word tags.

When clicking on tags with multiple words (tags with spaces in them -
ex: "ruby rails"), spaces are also displayed in URL.

How do I eliminate those spaces in URL?. I tried using permalink, by
creating a Tag model but it didn't work.

Any ideas?