First you need a Nokia or a Sony Ericsson mobile phone which supports SyncML over OBEX. Currently these should be Nokia (3220, 6220,)? 6230, 6620, 6630, 6810, 6820, 7610, 9500 and Sony Ericsson K500, K700, S700, V800, Z1010. The Nokia 6650 and 7600 do not have it. Then you have to pair both devices and from the computer you have to browse for the SyncML Client Bluetooth profile. You might need to search for it with its UUID (or OBEX, RFCOMM or L2CAP UUID) explicitly as it is not in the public browsable group on some Nokia phones.
Bind a serial port to this profile. Then you have to make an OBEX Connect as described within the SyncML OBEX Binding which contains very detailed examples at the end. Now you have to talk WBXML and send a Server Alerted Sync like this:
See my webpage for its WBXML representation.
<?xml version='1.0' encoding='UTF-8' standalone='yes'?>
<!DOCTYPE SyncML PUBLIC
'-//OMA//DTD SYNCML 1.1//EN'
see SyncML Sync Protocol, version 1.1.2; chapter 13.1 Sync Alert
<LocURI>GSM Remote ML</LocURI>
The ‘Final’ element of the SyncML package must be within a End-of-body OBEX header. This seems to be one of the various bugs of the current Nokia SyncML OBEX server. These are all MIME types I know which work with these mobile phones. Note that the MIME types are case-sensitive within the SyncML client - again a bug of Nokia.
If you have problems with SyncML, first start a search at the archive of its Yahoo group. A lot of problems (most with SyncML over HTTP) are discussed there already.