You can use the root node's Alternate_Specular input to plug in alternate methods for computing surface highlights (specularity).

You will usually want to lower the standard Highlight_Color or Highlight_Value attributes to nearly black (zero) so that the alternative diffuse lighting node will be responsible for most of the specular lighting effect.

Nodes that perform alternate specular lighting include blinn, glossy, and anisotropic.

The Alternate_Specular input's effect is not affected by the root node's transparency settings.