diff --git a/common.mk b/common.mk
index 43097731..7dee4727 100644
--- a/common.mk
+++ b/common.mk
@@ -61,7 +61,7 @@ CHISEL_ARGS ?=
 
 $(FIRRTL_FILE) $(ANNO_FILE): $(SCALA_SOURCES) $(sim_dotf)
 	mkdir -p $(build_dir)
-	cd $(base_dir) && $(SBT) "runMain $(PROJECT).Generator $(CHISEL_ARGS) $(build_dir) $(PROJECT) $(MODEL) $(CFG_PROJECT) $(CONFIG)"
+	cd $(base_dir) && $(SBT) "project $(SBT_PROJECT)" "runMain $(PROJECT).Generator $(CHISEL_ARGS) $(build_dir) $(PROJECT) $(MODEL) $(CFG_PROJECT) $(CONFIG)"
 
 #########################################################################################
 # create verilog files rules and variables
diff --git a/variables.mk b/variables.mk
index f44286c5..c944af1c 100644
--- a/variables.mk
+++ b/variables.mk
@@ -9,6 +9,7 @@
 #   MODEL = the top level module of the project (normally the harness)
 #   CONFIG = the configuration class to give the parameters for the project
 #   CFG_PROJECT = the scala package to find the CONFIG class
+#   SBT_PROJECT = the SBT project that you should find the Generator class in
 #   TB = wrapper over the TestHarness needed to simulate in VCS
 #   TOP = top level module of the project (normally the module instantiated by the harness)
 #########################################################################################
@@ -16,6 +17,7 @@ PROJECT     ?= example
 MODEL       ?= TestHarness
 CONFIG      ?= DefaultExampleConfig
 CFG_PROJECT ?= $(PROJECT)
+SBT_PROJECT ?= $(PROJECT)
 TB          ?= TestDriver
 TOP         ?= ExampleTop