qm clone gives unable to parse volume ID

I tried to clone a vm with the command line, by
qm clone 101 103 -name WebServerNew -format raw -full 1
but got "unable to parse volume ID '/dev/disk/by-id/scsi-SATA_WDC_WD40EFRX-68_WD-WCC4EHJF6HLX-part1'"

This partition is a raw mapping into my virtual machine:
virtio7: /dev/disk/by-id/scsi-SATA_WDC_WD40EFRX-68_WD-WCC4EHJF6HLX-part1,backup=no

It seems the regular expression in /usr/share/perl5/PVE/Storage/Plugin.pm:185 does not support this.
a) Is this a bug?
b) If no, what is the preferred way to do such a raw mapping?

BR
Jasmin