Bricks, Masonry, Asphalt and Concrete - Brick moisture

I purchased a new house that has brick steps leading to a porch. After every rain there is a bit of water that comes fron the junction of the bottom of the brick steps where it meets the sidewalk. The mortar at the bottom of the stairs becomes damp as does about the first 2 feet of sidewalk. This mortar and sidewalk remain wet for several days after mositure has evaporated for all other cement surfaces. The brick steps are actually built so that the are resting on top of the sidewalk.

I am not sure where the water is coming from, but am currently thinking that the bricks are absorbing water and that normally the moisture settles into the ground, however, since the brick steps are built on the sidewalk the cement sidewalk is so dense that the moisture can not get through the sidewalk and the path of least resistence is such that the moisture flows through the mortar at the front of the steps.

Any thoughts on where the water is coming from?
Are there any long term potential problems from the moisture being in the cement and mortar for an extended period of time?

Should I seal the bricks?
Does sealing the bricks cause long term damage?
Will sealing the bricks make them slippery?

Any thoughts would be appreciated.

Thanks
Doug

Your message was answered

http://forum.doityourself.com/showthread.php?s=&threadid=127209

in that reply you suggested it was subsurface water. I replied to that message as to why it is not, I believe, subsurface water and am trying to get other opinions.

Thanks
Doug