{x10_id} not set in MH 3.1 for X10MS motion sensors

[hollie]

As reported by Giles through the mailing list:

During my upgrade to Misterhouse 3.1 I noticed that devices set up as X10MS in items.mht don’t seem to have their {x10_id} set any more, clearly a workaround is to set them myself but its a but annoying.
e.g.
items.mht
X10MS, D5, Back_hall_MS13PIR, X10_item, MS13

Code to test if {x10_id} correctly set - in a loop through all X10_items;

print_log("found this list item $item->{x10_id} , $item->{object_name}");

Gives
30/08/2014 15:04:28 found this list item , $Back_hall_MS13PIR
where I would have expected;
30/08/2014 15:04:28 found this list item D5 , $Back_hall_MS13PIR