"2-weapon fighting"

[SwiftyKun]

Hey all. I had an interesting idea and wanted to see if it is viable and works. My Paladin character usually uses a greatsword so he can use LoH on himself and others. However, it's gotten to the point where I need more AC. I decided to ditch the greatsword, and now my paladin has a long sword, spiked small shield(So I can still use LoH), and armor spikes. According to the rules, I can bash with my spiked shield as a martial weapon, but I lose it's AC bonus for the time being. I can also use my armor spikes as a light weapon, off-handed or main-handed. If I took the two-weapon fighting feat, making my penalties for "dual-wielding" -2/-2, can I smite evil an enemy target, then attack him dual-wielding my main-hand longsword and light weapon off-hand armor spikes while still retaining my light shield's AC bonus?

[Tarantula]

Yes you can.

[Nefreet]

Yes.

[Chess Pwn]

improved shield bash lets you use your shield to bash and keep the AC from it.

[Captain Sir Hexen Ineptus]

Paladins don't exactly have a lot of feats.

[Rodinia]

Another way to get extra attacks while smiting, which I presume is your goal, is to wield a reach weapon and take AoOs.

[Seranov]

You can.

There is some "metaphorical hand" nonsense going on with TWF and armor spikes, but since you are using the Longsword in one hand, with the other using a shield, you have a free "hand" with which to use the armor spikes.