The utility depends on the message file to have at minimum a Subject Header. There should be at least one blank line separating the Subject from the body. The other required headers are generated by the utility. The notification file format is the following:
Subject: [Warning] quota reached for %U% Hello %U%, Your quota: %C% Your current mailbox usage: %M% Your mailbox is now %Q% full. The folders consuming the most space are: %R%. Please clean up unwanted diskspace. Thanks, -Administrator
Localized versions of imquotacheck notification incorrectly convert the % and the $ signs. To correct the encoding, replace every $ with \24 and replace every % with \25 in the message file.