We are waiting for clarification / a clarification

Slight diff in meaning: "a" suggests something more specific. Otherwise I guess they're both okay....

Con, Man, Punk, Raz, help

They are equivalent. Colloquial usage, in the United States, at least, would drop the indefinite article. "Their latest offer was ambiguous; we are waiting for clarification.

Thanks, dalehileman and Setanta.

Tang you're most welcome, for what it's worth