--- a/stage3/fill_candidate_datatypes.hh	Tue May 20 08:25:59 2014 +0100
+++ b/stage3/fill_candidate_datatypes.hh	Thu May 29 12:06:22 2014 +0100
@@ -242,7 +242,6 @@
     /********************************************/
     /* B 1.6 Sequential function chart elements */
     /********************************************/
-
     void *visit(transition_condition_c *symbol);
 
     /********************************/

--- a/stage3/narrow_candidate_datatypes.cc	Tue May 20 08:25:59 2014 +0100
+++ b/stage3/narrow_candidate_datatypes.cc	Thu May 29 12:06:22 2014 +0100
@@ -817,17 +817,16 @@
 /********************************************/
 /* B 1.6 Sequential function chart elements */
 /********************************************/
-
 void *narrow_candidate_datatypes_c::visit(transition_condition_c *symbol) {
-	if (symbol->candidate_datatypes.size() != 1)
-		return NULL;
-	symbol->datatype = symbol->candidate_datatypes[0];
+	// We can safely ask for a BOOL type, as even if the result is a SAFEBOOL, in that case it will aslo include BOOL as a possible datatype.
+	set_datatype(&get_datatype_info_c::bool_type_name /* datatype*/, symbol /* symbol */);
+
 	if (symbol->transition_condition_il != NULL) {
-		symbol->transition_condition_il->datatype = symbol->datatype;
+		set_datatype(symbol->datatype, symbol->transition_condition_il);
 		symbol->transition_condition_il->accept(*this);
 	}
 	if (symbol->transition_condition_st != NULL) {
-		symbol->transition_condition_st->datatype = symbol->datatype;
+		set_datatype(symbol->datatype, symbol->transition_condition_st);
 		symbol->transition_condition_st->accept(*this);
 	}
 	return NULL;

--- a/stage3/narrow_candidate_datatypes.hh	Tue May 20 08:25:59 2014 +0100
+++ b/stage3/narrow_candidate_datatypes.hh	Thu May 29 12:06:22 2014 +0100
@@ -222,7 +222,6 @@
     /********************************************/
     /* B 1.6 Sequential function chart elements */
     /********************************************/
-
     void *visit(transition_condition_c *symbol);
 
     /********************************/

--- a/stage3/print_datatypes_error.cc	Tue May 20 08:25:59 2014 +0100
+++ b/stage3/print_datatypes_error.cc	Thu May 29 12:06:22 2014 +0100
@@ -689,6 +689,18 @@
 }
 
 
+/********************************************/
+/* B 1.6 Sequential function chart elements */
+/********************************************/
+void *print_datatypes_error_c::visit(transition_condition_c *symbol) {
+	if (symbol->transition_condition_il != NULL)   symbol->transition_condition_il->accept(*this);
+	if (symbol->transition_condition_st != NULL)   symbol->transition_condition_st->accept(*this);
+
+	if (!get_datatype_info_c::is_type_valid(symbol->datatype))
+		STAGE3_ERROR(0, symbol, symbol, "Transition condition has invalid data type (should be BOOL).");
+	return NULL;
+}
+
 
 /********************************/
 /* B 1.7 Configuration elements */
@@ -1163,7 +1175,7 @@
 	symbol->expression->accept(*this);
 	if ((!get_datatype_info_c::is_type_valid(symbol->expression->datatype)) &&
 	    (symbol->expression->candidate_datatypes.size() > 0)) {
-		STAGE3_ERROR(0, symbol, symbol, "Invalid data type for 'IF' condition.");
+		STAGE3_ERROR(0, symbol, symbol, "Invalid data type for 'IF' condition (should be BOOL).");
 	}
 	if (NULL != symbol->statement_list)
 		symbol->statement_list->accept(*this);
@@ -1178,7 +1190,7 @@
 	symbol->expression->accept(*this);
 	if ((!get_datatype_info_c::is_type_valid(symbol->expression->datatype)) &&
 	    (symbol->expression->candidate_datatypes.size() > 0)) {
-		STAGE3_ERROR(0, symbol, symbol, "Invalid data type for 'ELSIF' condition.");
+		STAGE3_ERROR(0, symbol, symbol, "Invalid data type for 'ELSIF' condition (should be BOOL).");
 	}
 	if (NULL != symbol->statement_list)
 		symbol->statement_list->accept(*this);

--- a/stage3/print_datatypes_error.hh	Tue May 20 08:25:59 2014 +0100
+++ b/stage3/print_datatypes_error.hh	Thu May 29 12:06:22 2014 +0100
@@ -203,6 +203,11 @@
     /**********************/
     void *visit(program_declaration_c *symbol);
 
+    /********************************************/
+    /* B 1.6 Sequential function chart elements */
+    /********************************************/
+    void *visit(transition_condition_c *symbol);
+
     /********************************/
     /* B 1.7 Configuration elements */
     /********************************/