incomplete attachment using GL_TEXTURE_2D_ARRAY with depth component

Question

I'm trying to use opengl texture arrays for storing a lot of shadow maps. Unfortunately, I always get an "incomplete attachment" error on checking the framebuffer. I tried to set up my texture array like in nvidia's cascaded shadow mapping example (see Cascaded Shadow Mapping example by NVIDIA).

So here's some code:

1. creating the texture:

   glGenTextures(1, &shadowMapArray_);
   glBindTexture(GL_TEXTURE_2D_ARRAY, shadowMapArray_);
   //maxArrayDepth_ = GL_MAX_ARRAY_TEXTURE_LAYERS
   glTexImage3D(GL_TEXTURE_2D_ARRAY, 0, GL_DEPTH_COMPONENT, size_, size_, maxArrayDepth_, 0, GL_DEPTH_COMPONENT, GL_FLOAT, 0);
   glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
   glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
   glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
   glTexParameteri(GL_TEXTURE_2D_ARRAY, GL_TEXTURE_COMPARE_FUNC, GL_LESS);
   glBindTexture(GL_TEXTURE_2D_ARRAY, 0);
   

2. create FBO:

   glGenFramebuffers(1, &fbo_);
   glBindFramebuffer(GL_FRAMEBUFFER, fbo_);
   glDrawBuffer(GL_NONE);
   glBindFramebuffer(GL_FRAMEBUFFER, 0);
   

3. draw shadow map into layer:

   glUseProgram(programID_);
   glBindFramebuffer(GL_FRAMEBUFFER, fbo_);
   glFramebufferTextureLayer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, shadowMapArray_, 0, currArraySize_);
   GLView::checkGLFramebuffer("ShadowMapGenerator::createShadowMap()"); //here i get the incomplete attachment
   [...]
   currArraySize_++;
   

System specs:

Debian Squeeze 64bit with Nvidia driver 304.60 and a GTX 560 Ti. The old driver version is due to a shader compiler bug in the newer versions.