Texture paint mode problems?

Using texture paint mode in the 3d window doesnt seem to work properly for me, it sort of paints in spots where the brush isnt, and leaves lines where the uvs are seperated unless i keep going over it to get rid of the lines… Well its kind of hard to explain.

Or here is a screen. I have only painted on the top of monkeys head, but the paint has also gone on the ear and top of the eye, you can also see the lines at the edge of the uv section thing. Any ideas.

How nice is your unwrap? In your choice of unwrap method, did you use mark seams and make clustered islands or use the smart projections unwrap? I had similar problems before I concentrated on getting a good unwrap - seems that if the uv’s are on top of each other, then the paint will likely show in different spots because it is being painted onto one image in the editor - the verts map through uv coordinates to the image, so painting in 3d space on a coordinate also paints onto another face inthe same 3d view because the uv’s are overlapping.

As to the line issue, perhaps your image is too low resolution for the paint? Shot in the dark though, could be driver issue as well I suppose.

It looks like a bad unwrap to me. The paint tool just takes the point where you click on the object and applies that to the image map. If your UV map is split up all over the place, that spot on your texture map may be very close to another texture island and color will spill over.