StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
StrBufAppendBuf(BounceMB, boundary, 0);
StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);
StrBufAppendBufPlain(BounceMB, HKEY("--"), 0);
StrBufAppendBuf(BounceMB, boundary, 0);
StrBufAppendBufPlain(BounceMB, HKEY("--\r\n"), 0);