problems using compressed textures

hi guys, i’ve got a problem using compressed DXT1 textures, here’s a description of what i’m doing:
i’m reading a DDS file with a DXT1 compressed image, when i pass it to glCompressedTexImage2dARB it gives me a black texture. i think all the parameters are correct, its a 256x256 RGB image with a data size of 32768 bytes, the internal format i’m passing is GL_COMPRESSED_RGB_S3TC_DXT1_EXT, what’s wrong with what i’m doing?

problem solved, there was a bug in my code that changed the texture size parameters to wrong values.