Not really. The thing is, the SQL engine needs to be able to decrypt the procedure in order to compile and run it, so you can't use some third party form of encryption unless you can modify the SQL engine itself.
Does the SQL server that the procedures are going on to belong to your client?
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)SQL In The Wild
: Discussions on DB performance with occasional diversions into recoverability
We walk in the dark places no others will enter
We stand on the bridge and no one may pass