Being a nonnative speaker of English, I'm very happy that recently people have been more open to the fact that nonnative English-speaking teachers can be good English teachers. In fact some people even state that nonnative speakers are better teachers, because they have had to learn English themselves.
Here some extracts from the following article:
"Native English speakers without teaching qualifications are more likely to be hired as ESL teachers than qualified and experienced NNESTs, especially outside the United States. But many in the profession argue that teaching credentials should be required of all English teachers, regardless of their native language. This would shift the emphasis in hiring from who the job candidates are (i.e., native or nonnative speakers of English) to what they are (i.e., qualified English teachers) and allow for more democratic employment practices.
Phillipson (1996) considers NNESTs to be potentially the ideal ESL teachers because they have gone through the process of acquiring English as an additional language. They have first-hand experience in learning and using a second language, and their personal experience has sensitized them to the linguistic and cultural needs of their students. Many NNESTs, especially those who have the same first language as their students, have developed a keen awareness of the differences between English and their students’ mother tongue. This sensitivity gives them the ability to anticipate their students’ linguistic problems.
Issues of teacher credibility are encountered by many NNESTs in the classroom, where even students are influenced by the inevitable trickle-down effect of the native speaker fallacy. Some NNESTs have reported that many of their students resented being taught by a nonnative speaker until they were able to prove that they could be as effective as a native-English-speaking teacher. In reality, speakers of more than one language have both a sophisticated awareness of language and the ability to relate to students’ needs. "