ftp://ftp.symantec.com/public/english_us_canada/liveupdate/luadmin.pdf
Download and check here, but from what I know, it doesn't appear possible to do this. You'd have to go into Services in Windows and disable the server there.
If you are comfortable with what you're doing, you could create a policy and apply this to all the servers that do backups in your domain. Just be sure to test it thoroughly. This policy would then disable that service automatically once the policy is applied.
