How to start mrxvt maximized?

[blixel]

There needs to be a command line section. But, I'm wanting to know how to do this for Desktop purposes, so this category will have to suffice.

As the subject says, I want to start mrxvt so that it is already maximized. I'm using OpenBox as my Window Manager, but I'm not sure if that matters. Basically, when I right click on the root window (a.k.a. the Desktop), and go to my Terminals menu, I want to have one setup where I can start mrxvt so that when it opens, it's all ready as though I pressed the maximize button. Currently I'm just using the --geometry switch to achieve a near maximized window, but it's not fully maximized, and if I change resolutions, the geometry settings have to be reconfigured.