Add workaround for brain damaged cell phones

PR:		bin/67906

1 files changed, 18 insertions, 1 deletions

diff --git a/usr.sbin/bluetooth/rfcomm_pppd/rfcomm_pppd.8 b/usr.sbin/bluetooth/rfcomm_pppd/rfcomm_pppd.8
index 2369242..207f471 100644
--- a/usr.sbin/bluetooth/rfcomm_pppd/rfcomm_pppd.8
+++ b/usr.sbin/bluetooth/rfcomm_pppd/rfcomm_pppd.8
@@ -41,7 +41,7 @@
 .Fl u Ar N
 .Nm
 .Fl s
-.Op Fl dh
+.Op Fl dhS
 .Op Fl a Ar BD_ADDR
 .Fl C Ar channel
 .Fl l Ar label
@@ -126,6 +126,23 @@ Display usage message and exit.
 In both client and server modes, this required option specifies which
 .Xr ppp 8
 label will be used.
+.It Fl S
+In the server mode register the Serial Port (SP) service in addition to the
+LAN Access Using PPP (LAN) service.
+It appears that some cell phones are using so called
+.Dq callback mechanism .
+In this scenario the user is trying to connect his cell phone to the Internet,
+and, user's host computer is acting as the gateway server.
+It seems that it is not possible to tell the phone to just connect and start
+using the LAN service.
+Instead the user's host computer must
+.Dq jump start
+the phone by connecting to the phone's SP service.
+What happens next is the phone kills the existing connection and opens another
+connection back to the user's host computer.
+The phone really wants to use LAN service, but for whatever reason it looks
+for the SP service on the user's host computer.
+This brain damaged behavior was reported for Nokia 6600 and Sony/Ericsson P900.
 .It Fl s
 Act as an RFCOMM server.
 .It Fl u Ar N