Is speaking in tongues a sign of being born-again?

The baptism in the Holy Spirit is regarded as an experience that usually occurs after conversion. Pentecostals believe at conversion a Christian receives the Holy Spirit. However only at the subsequent baptism in the Holy Spirit does the Christian receive the fullness of the Spirit and the full empowerment for Christian service. Most Pentecostals believe that Spirit-baptism is always accompanied with the gift of speaking in tongues as evidence for the baptism. Thus one can be a genuine Christian yet not be baptised in the Holy Spirit.