diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 64766219f..bb9447c92 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -4,6 +4,7 @@ D1X-Rebirth Changelog
 --------
 arch/sdl/digi_mixer.c, arch/sdl/digi_mixer_music.c, arch/sdl/jukebox.c, d1x-rebirth.xcodeproj/project.pbxproj, main/multi.h: On Mac OS X - no longer have to copy SDL_mixer.h to SDL framework; frameworks can now be in /Library/Frameworks; fix for obscure compile error involving u_int32_t
 include/ogl_init.h, 2d/font.c, arch/ogl/ogl.c, arch/ogl/gr.c: Rewrote code to control Texture Filtering a little so it's easier to apply Mipmaps for different parts of the game independently
+main/gamecntl.c, main/menu.c, main/newdemo.c, main/newdemo.h: Using PHYSFSX_findFiles to make sure random demo playback will only find actual demo files and not quit autodemo; added DEMO_EXT for an universal definition of demo file extension
 
 20100901
 --------
diff --git a/main/gamecntl.c b/main/gamecntl.c
index 7d89f5ae0..45e07b1a3 100644
--- a/main/gamecntl.c
+++ b/main/gamecntl.c
@@ -441,7 +441,7 @@ int HandleDemoKey(int key)
 			c = newmenu_do( NULL, NULL, 2, m, NULL, NULL );
 			if (c == -2)
 				break;
-			strcat(filename, ".dem");
+			strcat(filename, DEMO_EXT);
 			num[0] = '\0';
 			m[ 0].type = NM_TYPE_TEXT; m[ 0].text = "strip how many bytes";
 			m[ 1].type = NM_TYPE_INPUT;m[ 1].text_len = 16; m[1].text = num;
diff --git a/main/menu.c b/main/menu.c
index 49d2e4fef..36c02ccc1 100644
--- a/main/menu.c
+++ b/main/menu.c
@@ -736,7 +736,7 @@ int demo_menu_handler( listbox *lb, d_event *event, void *userdata )
 int select_demo(void)
 {
 	char **list;
-	char *types[] = { ".dem", NULL };
+	char *types[] = { DEMO_EXT, NULL };
 	int NumItems;
 
 	list = PHYSFSX_findFiles(DEMO_DIR, types);
diff --git a/main/newdemo.c b/main/newdemo.c
index 5f5940a3d..be80f997f 100644
--- a/main/newdemo.c
+++ b/main/newdemo.c
@@ -3252,7 +3252,7 @@ try_again:
 		if (filename[0] != '\0') {
 			strcpy(save_file, DEMO_DIR);
 			strcat(save_file, filename);
-			strcat(save_file, ".dem");
+			strcat(save_file, DEMO_EXT);
 		} else
 			sprintf (save_file, "%stmp%d.dem", DEMO_DIR, tmpcnt++);
 		remove(save_file);
@@ -3278,7 +3278,7 @@ try_again:
 		strcat(fullname, m[1].text);
 	else
 		strcat(fullname, m[0].text);
-	strcat(fullname, ".dem");
+	strcat(fullname, DEMO_EXT);
 	PHYSFS_delete(fullname);
 	PHYSFSX_rename(DEMO_FILENAME, fullname);
 }
@@ -3287,9 +3287,10 @@ try_again:
 int newdemo_count_demos()
 {
 	char **find, **i;
+	char *types[] = { DEMO_EXT, NULL };
 	int NumFiles=0;
 
-	find = PHYSFS_enumerateFiles(DEMO_DIR);
+	find = PHYSFSX_findFiles(DEMO_DIR, types);
 
 	for (i = find; *i != NULL; i++)
 		NumFiles++;
@@ -3316,6 +3317,7 @@ void newdemo_start_playback(char * filename)
 		// Randomly pick a filename
 		int NumFiles = 0, RandFileNum;
 		rnd_demo = 1;
+		char *types[] = { DEMO_EXT, NULL };
 
 		NumFiles = newdemo_count_demos();
 
@@ -3326,7 +3328,7 @@ void newdemo_start_playback(char * filename)
 		RandFileNum = d_rand() % NumFiles;
 		NumFiles = 0;
 
-		find = PHYSFS_enumerateFiles(DEMO_DIR);
+		find = PHYSFSX_findFiles(DEMO_DIR, types);
 
 		for (i = find; *i != NULL; i++)
 		{
@@ -3345,13 +3347,6 @@ void newdemo_start_playback(char * filename)
 			GameArg.SysAutoDemo = 0;
 			return;
 		}
-
-		// if in random mode, PhysFS may look for all possible files, so check if filename actually points to be a demo file...
-		if (strnicmp(".dem",&filename2[strlen(filename2)-4],4))
-		{
-			GameArg.SysAutoDemo = 0;
-			return;
-		}
 	}
 
 	infile = PHYSFSX_openReadBuffered(filename2);
diff --git a/main/newdemo.h b/main/newdemo.h
index 3e4f3431c..538005dcb 100644
--- a/main/newdemo.h
+++ b/main/newdemo.h
@@ -32,6 +32,7 @@ COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
 #define ND_STATE_ONEFRAMEBACKWARD	7
 
 #define DEMO_DIR                "demos/"
+#define DEMO_EXT		".dem"
 #if WORDS_BIGENDIAN
 #define DEMO_BACKUP_EXT			"386"
 #else