diff --git a/Bootloaders/DFU/BootloaderDFU.c b/Bootloaders/DFU/BootloaderDFU.c
index 883afef03..18770e70d 100644
--- a/Bootloaders/DFU/BootloaderDFU.c
+++ b/Bootloaders/DFU/BootloaderDFU.c
@@ -135,22 +135,21 @@ void Application_Jump_Check(void)
 		/* Check if the device's BOOTRST fuse is set */
 		if (!(BootloaderAPI_ReadFuse(GET_HIGH_FUSE_BITS) & ~FUSE_BOOTRST))
 		{
-			/* If the reset source was not an external reset or the key is correct, clear it and jump to the application */
-			//if (!(MCUSR & (1 << EXTRF)) || (MagicBootKey == MAGIC_BOOT_KEY))
-			//  JumpToApplication = true;
+			/* If the reset source was a power on reset or a brown out reset or the key is correct, clear it and jump to the application */
+			if (MCUSR & ((1 << PORF) | (1 << BORF)) || (MagicBootKey == MAGIC_BOOT_KEY))
+			{
+				JumpToApplication = true;
+			}
 
-			/* Clear reset source */
-			MCUSR &= ~(1 << EXTRF);
+			/* Clear reset sources */
+			MCUSR &= ~((1 << PORF) | (1 << BORF));
 		}
 		else
 		{
-			/* If the reset source was the bootloader and the key is correct, clear it and jump to the application;
-			 * this can happen in the HWBE fuse is set, and the HBE pin is low during the watchdog reset */
-			//if ((MCUSR & (1 << WDRF)) && (MagicBootKey == MAGIC_BOOT_KEY))
-			//	JumpToApplication = true;
-
-			/* Clear reset source */
-			MCUSR &= ~(1 << WDRF);
+			/* If the reset source was the bootloader the key is correct. Jump to the application;
+			 * this can happen if the HWBE fuse is set, and the HWB pin is low during the watchdog reset */
+			if (MagicBootKey == MAGIC_BOOT_KEY)
+				JumpToApplication = true;
 		}
 	#endif
 
diff --git a/Bootloaders/DFU/makefile b/Bootloaders/DFU/makefile
index b9b7a73d4..d3ae8d926 100644
--- a/Bootloaders/DFU/makefile
+++ b/Bootloaders/DFU/makefile
@@ -43,6 +43,10 @@ BOOT_API_LD_FLAGS     = $(call BOOT_SECTION_LD_FLAG, .apitable_trampolines, Boot
 BOOT_API_LD_FLAGS    += $(call BOOT_SECTION_LD_FLAG, .apitable_jumptable,   BootloaderAPI_JumpTable,   32)
 BOOT_API_LD_FLAGS    += $(call BOOT_SECTION_LD_FLAG, .apitable_signatures,  BootloaderAPI_Signatures,  8)
 
+ifeq ($(strip $(CHECK_RESET_SOURCE)), yes)
+    OPT_DEFS += -DCHECK_RESET_SOURCE
+endif
+
 # Default target
 all:
 
diff --git a/LUFA/Build/DMBS/DMBS/gcc.mk b/LUFA/Build/DMBS/DMBS/gcc.mk
index 73065dcec..b8b61194f 100644
--- a/LUFA/Build/DMBS/DMBS/gcc.mk
+++ b/LUFA/Build/DMBS/DMBS/gcc.mk
@@ -136,6 +136,9 @@ ifeq ($(LTO), Y)
    BASE_CC_FLAGS += -flto -fuse-linker-plugin
    BASE_LD_FLAGS += -flto -fuse-linker-plugin
 endif
+ifneq ($(OPT_DEFS),)
+   BASE_CC_FLAGS += $(OPT_DEFS)
+endif
 
 # Additional language specific compiler flags
 BASE_C_FLAGS   := -x c -O$(OPTIMIZATION) -std=$(C_STANDARD) -Wstrict-prototypes