Multiple domains, Impact on engine ranking?

[Vulcan315]

How does one utilize additional domains that were purchased to protect from their use by the competition, without getting a search engine penalty as being perceived as duplicate content?

Can the additional domains simply be pointed at the main site via new "A" record, or forwarded be a service like mydomain.com without problems?

Thanks,
Dave

[Vulcan315]

...I think I may have answered my own question when I was reading a bunch of stuff here last night. I've set my additional domains to a 301 redirect to the main domain address. If this is correct, would someone just toss a note here or sticky me, I'd appreciate it muchly :-)

I also used the "Server Header Check" tool here and they all seem to be redirecting correctly, as best as I can tell.

Still have one problem to solve, if anyone knows how to do it... My searches on Y! for my site return the IP address, instead of the domain name. I think it may be costing me a duplicate content penalty of some sort. Anyway, I would like to have the use of the IP address to be redirected to the top domain name with a 301, but can't figure out what the string should be in the .htaccess file. I've experimented a bit, and found strings like:

redirect 301 [mydomain.com...]

..to redirect the ip address to the top domain (http://www.mydomain.com), but when I run a header check, www.mydomain.com is _also_ redirected as a 301...not good. I can't figure out what to put in the .htaccess string to include do something like this:

redirect 301 #$!@.IP.ad.rs [mydomain.com...]

...and actually make it work. I think I'm overlooking something, as the above string seems to do nothing.

As usual, any help is much appreciated!

Dave