diff -u a/member.c b/member.c
--- a/member.c	2010-10-06 14:06:30.000000000 +0200
+++ b/member.c	2010-11-17 14:38:14.306186436 +0100
@@ -775,8 +775,23 @@
 
 	// tell conference_exec we're ready for frames
 	member->ready_for_outgoing = 1 ;
+	int my_membercount = conf->membercount;
 	while ( 42 == 42 )
 	{
+		if ( my_membercount != conf->membercount ) 
+		{
+			// number of members has changed
+			if (my_membercount < conf->membercount && member->join_sound)
+			{
+				member_play_sound( member, member->join_sound );
+			}
+			else if (my_membercount > conf->membercount && member->leave_sound)
+			{
+				member_play_sound( member, member->leave_sound );
+			}
+			my_membercount = conf->membercount;
+		}
+
 		// make sure we have a channel to process
 		if ( chan == NULL )
 		{
@@ -1072,6 +1087,18 @@
 
 	// keep pointer to member's channel
 	member->chan = chan ;
+	
+	// check for enter/leave sounds
+	{
+		const char *tmp;
+		ast_channel_lock(chan);
+		member->join_sound = (tmp = pbx_builtin_getvar_helper(chan, "CONFERENCE_JOIN_SOUND")) ?
+			ast_strdup(tmp) : NULL;
+		member->leave_sound = (tmp = pbx_builtin_getvar_helper(chan, "CONFERENCE_LEAVE_SOUND")) ?
+			ast_strdup(tmp) : NULL;
+		ast_channel_unlock(chan);
+	}	
+	DEBUG("conference sounds: join '%s' leave '%s'\n", member->join_sound, member->leave_sound);
 
 	// set default if no type parameter
 	if (!member->type) {
@@ -1550,6 +1577,10 @@
 	// free the member's copy of the spyee channel name
 	free(member->spyee_channel_name);
 
+	// free join/leave sound file names (NULL if not set)
+	free(member->join_sound);
+	free(member->leave_sound);
+	
 	// clear all sounds
 	struct ast_conf_soundq *sound = member->soundq;
 	struct ast_conf_soundq *next;
@@ -3403,3 +3434,37 @@
 
 }
 #endif
+
+
+// Add sound file to a member's sound queue
+void member_play_sound ( struct ast_conf_member *member, const char *filename )
+{
+	struct ast_conf_soundq *newsound;
+	struct ast_conf_soundq **q;
+
+	newsound = calloc(1,sizeof(struct ast_conf_soundq));
+	if (newsound == NULL) {
+		perror("calloc for struct ast_conf_soundq failed");
+	}
+	else
+	{
+		newsound->stream = ast_openstream(member->chan, filename, member->chan->language);
+		if (newsound->stream)
+		{ 
+			member->chan->stream = NULL;
+			ast_copy_string(newsound->name, filename, sizeof(newsound->name));
+			// append sound to the end of the list.
+			for(q=&member->soundq; *q; q = &((*q)->next)) ;;
+			*q = newsound;
+			ast_log( LOG_VERBOSE, "Playing conference message %s to channel %s\n", filename, member->chan->name ) ;
+		}
+		else
+		{
+			char fmt[256];
+			ast_log(LOG_ERROR, "Unable to open %s (format %s): %s\n", 
+				filename, ast_getformatname_multiple(fmt, sizeof(fmt), member->chan->nativeformats), strerror(errno));
+			free(newsound);
+		}
+	}
+	ast_mutex_unlock(&member->lock);
+}
diff -u a/member.h b/member.h
--- a/member.h	2010-10-06 14:06:30.000000000 +0200
+++ b/member.h	2010-11-17 14:18:03.998186412 +0100
@@ -67,6 +67,11 @@
 	char *type ;		// conference type
 	char *spyee_channel_name ; // spyee  channel name
 	int max_users ; // zero or max users for this conference
+	
+	// sounds to play to the member when somebody joins/leaves the conference
+	char * join_sound; 
+	char * leave_sound;
+	
 #if ( SILDET == 2 )
 	// voice flags
 	int vad_flag;
@@ -319,6 +324,7 @@
 //
 
 int member_exec( struct ast_channel* chan, void* data ) ;
+void member_play_sound( struct ast_conf_member *, const char *) ;
 
 struct ast_conf_member* check_active_video( int id, struct ast_conference *conf );