I've been trying to update maemo 5 to version 3.2010.02-8 (92.2MB) , but using the application manager to download and install gives me the eroor message "insufficent space on destination drive".

Using the command line "apt-get update" does not download anything either and cloese with the following Warnings/Errors:
W: GPG error: http://moff.mozilla chinook Relase: The following signatures couldn't ve verified because the public key is not available: NO_PUBKEY 667387FBFFF445C24
E: Could not get lock /var/lib/dpkg/lock - open (11 Resouce temporariliy unavailable)
E: Uable to lock the administration directory (/var/lib/dpkg/), is another process using it?

Any ideas how I could procede?