If you want to extend a HDMI cable between your plasma and HD-DVD player CMI HET001 may help you to perform that task. For just £75 you will get a support HDCP and will able to send a 1080p signal up to 28m or a 1080i one up to 60m via CAT5. Sounds good, doesn’t it?
The CMI HET001 supports more or less fresh version of HDMI – 1.3 (there is a latest one 1.3b). So, it’ll be enough for the next two – three years minimum.