how as wh-NP

In standard American English, how is not acceptable as a relative pronoun (cf. (224)).

(223)0(223

(224)

*the way [how [$\epsilon$_C [PRO to solve this problem]]] 

However, ((224)) is accepted by the current grammar. The only way to rule ((224)) out would be to introduce a special feature devoted to this purpose. This is unappealing. Further, there exist speech registers/dialects of English, where ((224)) is acceptable.