The vchkuser qmail-spp plugin checks for recipient existence with vpopmail. It is based on a script by Werner Maier (http://www.maiers.de/qmail/art38,71.html) but has been rewritten in C to get rid of all the suid hacks and to enhance performance.
Commercial Use
Modify
Distribute
Place Warranty
Hold Liable
Use Trademarks
Include Copyright
Include License
These details are provided for information only. No information here is legal advice and should not be used as such.