Certain employer contributions treated as wages
Nothing in any paragraph of subsection (a) (other than paragraph (1)) shall exclude from the term “wages”—
(A) any employer contribution under a qualified cash or deferred arrangement (as defined in section 401(k)) to the extent not included in gross income by reason of section 402(e)(3) or consisting of designated Roth contributions (as defined in section 402A(c)), or
(B) any amount treated as an employer contribution under section 414(h)(2) where the pickup referred to in such section is pursuant to a salary reduction agreement (whether evidenced by a written instrument or otherwise).