The Collaborative International Dictionary of English v.0.48:

Mess \Mess\, v. i. [imp. & p. p. Messed; p. pr. & vb. n.
   Messing.]
   To take meals with a mess; to belong to a mess; to eat (with
   others); as, I mess with the wardroom officers. --Marryat.
   [1913 Webster]