Sound of open string applies to sharp note too, but it shouldn't

While composing or during playback, low E, A, D and G sound with a different pitch, like an open string on a real instrument. I'm talking about electric bass.

1) This behaviour should be configurable; many bass learners are told to avoid open strings.
2) The "open sound" can be heard even if that note is sharpened, and it shouldn't be.