I think that the only remaining step I didn't tried yet is restarting nfs client and/or related processes on eprod. Unfortunately I don't have the knowledge to do that.

Could you provide some commands for restarting nfs client service on Solaris 8 (and 10)? I've googled around but my greatest concern is disabling something vital or hampering current connections between clients and eprod, because also on eprod there could be something shared with nfs that other clients may be accessing.