Did you set up forwarding or cloaking? I thought you wanted cloaking/masking?
If you're cloaked and there aren't any links to yoursubdomain.awardspace.com, then search engines should pick up just your original domain. There's a slight danger that search engines will pick up both domains and yeah, you'd have to get someone to advise you on the meta tags or robots.txt entries that would prevent that.
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