"Someone has sent this message to our wives."

Translation: Někdo našim manželkám poslal tuto zprávu.

[cptlangstrumpf]

is it not possible to say "nekdo poslal tuto zpravu do nasim manzelkam"?

[endless_sleeper]

Nope.

1) Do is used with genitive, not dative.

2) Do means 'into/in' (a place, a location) or 'until/till' (a point in time).

[Reinhard693514]

Why is 'Někdo poslal našim ženám tento vzkaz' not accepted?

[VladaFu]

Because no one has reported anything with "vzkaz" yet.

[Reinhard693514]

So there is nothing wrong with my version as such?

[VladaFu]

no