In answer to your question, no, I have not used Dreamwave. In fact, a Google search reveals few hits and Google shopping showed no hits when I tried using the Dreamwave model number for the SIP-D28P unit. While I have no way to prove it, I am somewhat skeptical that Dreamwave is the OEM. The Yealink portfolio of phones is much larger and if you look at the support site under downloads, the Dreamwave site only shows downloads as recent as 2009. If they are indeed the manufacturer, it seems to me that they would have an even broader array of phones and be more prolific about their suppoprt. It almost appears as though they are the one who have rebranded the phones in order to present a complete product line in support of their IP-PBX offerings.
In any event, I have seen Yealink phones branded as Cortelco, Agnitel, Alloy, et al. The Yealink name seems to be the one most in use and they have suppport websites in various geographic areas of the world, so my guess is that Yealink is the parent.....but I could be wrong.
