postfix @xxxx.test files showing up in deferred

[Ron E.]

Just wondering if anyone else running postfix + mailscanner has noticed
this - I have recently had some zero byte files showing up in the incoming
postfix deferred directory. The files are named like:

@xxxxx.test

xxxxx = 5 digit number

Whenever the incoming postfix is reloaded I get some errors about these
files that look like this:

warning: valid_hostname: invalid character 64(decimal): @xxxxx.test

Just wondering if these can be safely removed or what.

Regards,

Ron