Has anyone come across this phrase as in an ad ergam diplomatic agreement and if so, can they pse tell me what it means?

Has anyone come across the phrase ad ergam as in an ad ergam diplomatic agreement and if so, do they know what it means?

Erga is a preposition in Latin so it wouldn't be declined. I googled ad-ergam and got a few hits on adergam in Portuguese and one where adergam was part of an email address and seems to be split up a dergam.

So I dunno.

[opening mouth and removing all doubt e] it wouldn't be declined. So how come you don't say declinated?

so how come *you don't say orientated?

-joe (coming over there) friday

I backformed it from declension, not from declination.