The problem is that it's impossible to work your chest without also working your arms. So, you're essentially working your arms two days in a row.
Personally, I would move to a full-body workout twice a week. Move your rest day to Tuesday, and lift on Monday and Friday. Focus on compound lifts and you can do a lot of work in those two days.
For example, you could pick one of these routines:
http://www.exrx.net/Workouts/Workout1LTA.html
Do sets of 4x6 or 5x5 on Monday. Start with a 12-15 rep warmup with 50% of the weight of your max lift. Then, do 4 sets of 6 reps, or 5 of 5, with gradually increasing weight so that the last set is the hardest and heaviest. Rest about 2 minutes in between sets. Then on Friday, you can do 3x8 or 2x12. If you really want to speed it up, you can alternate two exercises to give your muscles more rest. For instance, I do these alternations:
Flat bench, then move immediately to bent over row. Rest 2 minutes. Repeat.
Decline bench, then move immediately to pullups. Rest 2 minutes. Repeat.
Dips, then move immediately to lateral raises. Rest 30 seconds. Repeat.
Doing that, you give the muscle groups a lot of recovery time because you're not using the same sets of muscles twice in a row, but you're still doing work. Makes the workout quicker and more compact.
Just a suggestion.