E-brake dash light...strange problem

Ok, here goes. I already searched on this topic but everything I found doesn't sound like my problem. The other day, my friend and I went to a local mud hole to play around. I got into a rut a few times and got tossed around pretty good (enough to throw some change and a pack of gum out of the ashtray). On the drive home I noticed that whenever I stopped for a light, the e-brake light on the dash would flicker, then come on. However, it only came on during a certain point while braking. If I mashed the pedal to the floor, it went off, and if I pushed the pedal slowly it stayed off. It only comes on when the pedal is about halfway down or so. And when it comes on it usually flickers like a lightbulb does if theres a bad connection. As soon as I let off the brake in that certain position, the light goes off.
I tried parking and putting the E-brake on, then letting it off and pushing it all the way down, but it still does it. I was wondering if somehow my rig is registering the e-brake being on when it is in fact not? Or if somehow I knocked a wire loose somewhere that might be triggering it or what? I'm completely lost at this point and am really hoping it's not an imbalance between the front and rear brakes or something to do with the master cylinder. I left the E-brake on tonight to see if that somehow will affect it.
Thanx for any and all help!!! BTW it's a '92 XJ, 4L, I6, NP231, 3" lift on 32's.

Clean out the underside and make sure there's no mud pulling the e-brake cable or binding it in any way. Low brake fluid will also trigger the light.

Also verify the connection of the wire on the brake master cylinder itself. Sometimes it needs a little cleaning.

pete

Ok, I checked the connection to the master cylinder and that appears to be fine, and the E-brake cables running to the drums aren't damaged in any way. I still have that darn light flickering on and off every now and then still. My next question is this. Could the light be triggered if there were debris in the rear drums? Such as mud, rocks, etc.? I'll check this next when I get a break in the weather. Thanx again for the replies.

The E-brake light isn't on the master cylinder. That's the brake failure light.

The parking brake switch is on the underside of the lever. Make sure there isn't something down there interfering either with it or the lever. Perhaps when you hit those bumps one of those coins or something fell down the slot.