Hey christmas present question.

I'm afraid the code doesn't support this use case. However, it should be possible to add it to dg_variables or the dg_scripts files.

You could pick a range of vnums and make sure they all exist. Non-existing ones you could create a generic lump of coal :-)
This is how Detta did it:

Name: 'random obj load', VNum: [ 1973], RNum: [ 618]
Trigger Intended Assignment: Objects
Trigger Type: Command , Numeric Arg: 3, Arg list: unwrap
Commands:
eval present %random.27%
eval present2 %present% * 1000
eval present3 %present2% + %random.4%
%send% %actor% You begin unwrapping the present.
%echoaround% %actor% %actor.name% begins unwrapping %actor.hisher% present.
wait 1 s
%load% obj %present3% %actor% inv
eval inv %actor.inventory%
%echo% As the wrapping falls apart, it reveals... %inv.shortdesc%.
%purge% %self%