diff --git a/vhdlpp/entity_elaborate.cc b/vhdlpp/entity_elaborate.cc
index b1858776b..8ae49c73c 100644
--- a/vhdlpp/entity_elaborate.cc
+++ b/vhdlpp/entity_elaborate.cc
@@ -139,6 +139,7 @@ int Entity::elaborate_ports_(void)
 
 		  cur_decl.msb = arr_type->dimension(0).msb();
 		  cur_decl.lsb = arr_type->dimension(0).lsb();
+		  cur_decl.signed_flag = arr_type->signed_vector();
 
 	    } else {
 		  cerr << get_fileline() << ": error: "
diff --git a/vhdlpp/entity_emit.cc b/vhdlpp/entity_emit.cc
index 21d711328..1302f5da9 100644
--- a/vhdlpp/entity_emit.cc
+++ b/vhdlpp/entity_emit.cc
@@ -88,6 +88,8 @@ int Entity::emit(ostream&out)
 		  break;
 		case VLOGIC:
 		  out << "wire logic ";
+		  if (cur->second.signed_flag)
+			out << "signed ";
 		  if (cur->second.msb != cur->second.lsb)
 			out << "[" << cur->second.msb
 			    << ":" << cur->second.lsb << "] ";
diff --git a/vhdlpp/parse_misc.cc b/vhdlpp/parse_misc.cc
index 31bc90252..2bd78e6e5 100644
--- a/vhdlpp/parse_misc.cc
+++ b/vhdlpp/parse_misc.cc
@@ -81,7 +81,7 @@ const VType* calculate_subtype(const char*base_name,
 
 	    range[0] = VTypeArray::range_t(left_val, right_val);
 
-	    VTypeArray*subtype = new VTypeArray(base_array->element_type(), range);
+	    VTypeArray*subtype = new VTypeArray(base_array->element_type(), range, base_array->signed_vector());
 	    return subtype;
       }
 
diff --git a/vhdlpp/vtype.cc b/vhdlpp/vtype.cc
index 33e4baa59..82c99e96f 100644
--- a/vhdlpp/vtype.cc
+++ b/vhdlpp/vtype.cc
@@ -29,12 +29,16 @@ const VTypePrimitive primitive_BIT     (VTypePrimitive::BIT);;
 const VTypePrimitive primitive_INTEGER (VTypePrimitive::INTEGER);;
 const VTypePrimitive primitive_STDLOGIC(VTypePrimitive::STDLOGIC);;
 
+const VTypeArray primitive_BIT_VECTOR(&primitive_BIT,      vector<VTypeArray::range_t> (1));
+const VTypeArray primitive_BOOL_VECTOR(&primitive_BOOLEAN, vector<VTypeArray::range_t> (1));
+
 void preload_global_types(void)
 {
       global_types[perm_string::literal("boolean")]   = &primitive_BOOLEAN;
       global_types[perm_string::literal("bit")]       = &primitive_BIT;
       global_types[perm_string::literal("integer")]   = &primitive_INTEGER;
       global_types[perm_string::literal("std_logic")] = &primitive_STDLOGIC;
+      global_types[perm_string::literal("bit_vector")]= &primitive_BOOL_VECTOR;
 }
 
 void import_ieee(void)
@@ -51,11 +55,11 @@ static void import_ieee_use_numeric_bit(perm_string name)
 
       if (all_flag || name == "signed") {
 	    vector<VTypeArray::range_t> dims (1);
-	    global_types[perm_string::literal("signed")] = new VTypeArray(&primitive_STDLOGIC, dims);
+	    global_types[perm_string::literal("signed")] = new VTypeArray(&primitive_STDLOGIC, dims, true);
       }
       if (all_flag || name == "unsigned") {
 	    vector<VTypeArray::range_t> dims (1);
-	    global_types[perm_string::literal("unsigned")] = new VTypeArray(&primitive_BIT, dims);
+	    global_types[perm_string::literal("unsigned")] = new VTypeArray(&primitive_BIT, dims, false);
       }
 }
 
@@ -127,8 +131,8 @@ void VTypePrimitive::show(ostream&out) const
       }
 }
 
-VTypeArray::VTypeArray(const VType*element, const vector<VTypeArray::range_t>&r)
-: etype_(element), ranges_(r)
+VTypeArray::VTypeArray(const VType*element, const vector<VTypeArray::range_t>&r, bool sv)
+: etype_(element), ranges_(r), signed_flag_(sv)
 {
 }
 
@@ -154,6 +158,8 @@ void VTypeArray::show(ostream&out) const
 	    out << "(" << cur->msb() << " downto " << cur->lsb() << ")";
       }
       out << " of ";
+      if (signed_flag_)
+	    out << "signed ";
       if (etype_)
 	    etype_->show(out);
       else
diff --git a/vhdlpp/vtype.h b/vhdlpp/vtype.h
index c22b413d4..4a2984785 100644
--- a/vhdlpp/vtype.h
+++ b/vhdlpp/vtype.h
@@ -108,7 +108,7 @@ class VTypeArray : public VType {
       };
 
     public:
-      VTypeArray(const VType*etype, const std::vector<range_t>&r);
+      VTypeArray(const VType*etype, const std::vector<range_t>&r, bool signed_vector =false);
       ~VTypeArray();
 
       void show(std::ostream&) const;
@@ -117,12 +117,15 @@ class VTypeArray : public VType {
       const range_t&dimension(size_t idx) const
       { return ranges_[idx]; }
 
+      bool signed_vector() const { return signed_flag_; }
+
       const VType* element_type() const;
 
     private:
       const VType*etype_;
 
       std::vector<range_t> ranges_;
+      bool signed_flag_;
 };
 
 #endif