HI, i have a unity server 5.0 unified messaging with microsoft exhange server 7. My i install forefront in the unity server?, i'm asking because it is no included in the software compatibility matrix for Unity 5.0.
You can do anything you want; however, if you ever want TAC support on it the answer is no. Installing anything not explicitly listed on the compatibility matrix puts you in an unsupported state. This even applies to versions. If the matrix for Unity 5.0 only lists version X of software Y, then that's all you can officially install.