If the phase of the speaker response is similar, then I think there is no problem. Do you know the past of the speaker response? There might be no problem anyway; phase often does not matter, but it can.
EDIt: Not sure what you mean by phase error of a speaker, but speakers have phase shifts just as other electronic components do. In fact the phase response of a speaker can be complicated. I think Eminence has phase plots for many of its speakers.