Miler Saw bottom crack

[Steven Hsieh]

I was cleaning out my ryobi TS1342L mitler saw (http://www.homedepot.com/Tools-Hardware-Power-Tools-Saws/h_d1/N-5yc1vZ1xhcZas2t/R-100634340/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053), and notice these crack. Does anyone know what can cause this to happen? Already contacted Ryobi, should get answers tomorrow.

http://i628.photobucket.com/albums/uu5/hayashiox/Picture107-1.jpg

http://i628.photobucket.com/albums/uu5/hayashiox/Picture117.jpg

http://i628.photobucket.com/albums/uu5/hayashiox/Picture119-1.jpg

[Karl Brogger]

Does the crack go all the way through? Kinda looks like just an imperfect casting and not an actual crack.