mipmapping and BASE_LOD

I get the following strange(?) behaviour:I create a texture set min and mag filter to LINEAR_MIPMAP_LINEAR and LINEAR and also BASE_LOD and MAX_LOD to some values.THen I call gluBuild2DMipmaps to create the mipmaps.Code follows:

/create the texture/
/initialize texture/


Now when baselevel is anything greater than 0 the texture looks distorted(that is it just bares some resemblance to the initial texture).Setting maxlevel works fine though.Also if I use a mipmap generator of my own and just create and load all mipmaps between baselevel and maxlevel I get an error from the driver saying it failed to upload the texture and level 0 of the texture is some sort of a tiled MESA logo.The other level(s) are distorted as with gluBuild2DMipmaps.Is this normal or a driver bug?According to the specs I only need to upload levels baselevel to maxlevel to get a mipmap complete texture.