There is actually a short section in the help page about MySpace:
"However some community sites, like MySpace, do not allow adding
iframes or JavaScript, in those cases a link is the only solution.
That can be done by using the Generate Raw URL button or the Generate
W3C URL button (for a W3C compliant URL)."
Source:
http://www.7is7.com/otto/countdhelp.html
I have tried it myself on MySpace and did not find an easy way around
the blocking of iframes or JavaScript (this was some time ago, but I
am pretty sure it hasn't changed). You could complain to MySpace about
their policy, but I doubt they will listen, which just leaves you with
the link option, or make a page on your personal website and link to
that from your myspace account.
Otto