diff --git a/src/apps/icon-o-matic/generic/property/view/PropertyListView.cpp b/src/apps/icon-o-matic/generic/property/view/PropertyListView.cpp
index 436202103f..d43d6087f2 100644
--- a/src/apps/icon-o-matic/generic/property/view/PropertyListView.cpp
+++ b/src/apps/icon-o-matic/generic/property/view/PropertyListView.cpp
@@ -11,7 +11,6 @@
 #include <stdio.h>
 #include <string.h>
 
-#include <ClassInfo.h>
 #include <Clipboard.h>
 #ifdef __HAIKU__
 #  include <LayoutUtils.h>
@@ -191,8 +190,8 @@ PropertyListView::MessageReceived(BMessage* message)
 				if (!archivable)
 					continue;
 				// see if this is actually a property
-				Property* property = cast_as(archivable, Property);
-				if (!property || !propertyObject.AddProperty(property))
+				Property* property = dynamic_cast<Property*>(archivable);
+				if (property == NULL || !propertyObject.AddProperty(property))
 					delete archivable;
 			}
 			if (propertyObject.CountProperties() > 0)
diff --git a/src/apps/mail/ComboBox.cpp b/src/apps/mail/ComboBox.cpp
index fccc89c775..a9c60f34fa 100644
--- a/src/apps/mail/ComboBox.cpp
+++ b/src/apps/mail/ComboBox.cpp
@@ -64,7 +64,6 @@ All rights reserved.
 */
 
 #include <Button.h>
-#include <ClassInfo.h>
 #include <Debug.h>
 #include <InterfaceDefs.h>
 #include <ListItem.h>
@@ -613,8 +612,7 @@ BComboBox::TextInput::KeyDown(const char *bytes, int32 numBytes)
 
 	switch (aKey) {
 		case B_RETURN:
-			cb = cast_as(Parent(), BComboBox);
-
+			cb = dynamic_cast<BComboBox*>(Parent());
 			ASSERT(cb);
 
 			if (!cb->IsEnabled())
@@ -639,7 +637,7 @@ BComboBox::TextInput::KeyDown(const char *bytes, int32 numBytes)
 			}
 			break;
 		case B_TAB:
-//			cb = cast_as(Parent(), BComboBox);
+//			cb = dynamic_cast<BComboBox*>Parent());
 //			ASSERT(cb);
 //			if (cb->fAutoComplete && cb->fCompletionIndex >= 0) {	
 //				int32 from, to;
@@ -678,10 +676,10 @@ BComboBox::TextInput::KeyDown(const char *bytes, int32 numBytes)
 #if 0
 		case B_UP_ARROW:		// fall through
 		case B_DOWN_ARROW:
-			cb = cast_as(Parent(), BComboBox);
+			cb = dynamic_cast<BComboBox*>(Parent());
 			ASSERT(cb);
 			if (cb->fChoiceList) {
-				cb = cast_as(Parent(), BComboBox);
+				cb = dynamic_cast<BComboBox*>(Parent());
 				ASSERT(cb);
 				if (!(cb->fPopupWindow)) {
 					cb->fPopupWindow = cb->CreatePopupWindow();
@@ -709,11 +707,11 @@ BComboBox::TextInput::KeyDown(const char *bytes, int32 numBytes)
 			break;
 #endif
 		case B_ESCAPE:
-			cb = cast_as(Parent(), BComboBox);
+			cb = dynamic_cast<BComboBox*>(Parent());
 			ASSERT(cb);
 			if (cb->fChoiceList)
 			{
-				cb = cast_as(Parent(), BComboBox);
+				cb = dynamic_cast<BComboBox*>(Parent());
 				ASSERT(cb);
 				if (cb->fPopupWindow && cb->fPopupWindow->Lock())
 				{
@@ -749,7 +747,7 @@ BComboBox::TextInput::MakeFocus(bool state)
 	if (state == IsFocus())
 		return;
 
-	BComboBox* parent = cast_as(Parent(), BComboBox);
+	BComboBox* parent = dynamic_cast<BComboBox*>(Parent());
 	ASSERT(parent);
 
 	BTextView::MakeFocus(state);
diff --git a/src/preferences/sounds/HWindow.cpp b/src/preferences/sounds/HWindow.cpp
index d6295517e2..eed9cf3f66 100644
--- a/src/preferences/sounds/HWindow.cpp
+++ b/src/preferences/sounds/HWindow.cpp
@@ -19,7 +19,6 @@
 #include <Beep.h>
 #include <Box.h>
 #include <Button.h>
-#include <ClassInfo.h>
 #include <FindDirectory.h>
 #include <fs_attr.h>
 #include <MediaFiles.h>
@@ -173,7 +172,10 @@ HWindow::MessageReceived(BMessage* message)
 	switch (message->what) {
 		case M_OTHER_MESSAGE:
 		{
-			BMenuField* menufield = cast_as(FindView("filemenu"), BMenuField);
+			BMenuField* menufield
+				= dynamic_cast<BMenuField*>(FindView("filemenu"));
+			if (menufield == NULL)
+				return;
 			BMenu* menu = menufield->Menu();
 
 			HEventRow* row = (HEventRow*)fEventList->CurrentSelection();
@@ -199,8 +201,10 @@ HWindow::MessageReceived(BMessage* message)
 			entry_ref ref;
 			HEventRow* row = (HEventRow*)fEventList->CurrentSelection();
 			if (message->FindRef("refs", &ref) == B_OK && row != NULL) {
-				BMenuField* menufield = cast_as(FindView("filemenu"),
-					BMenuField);
+				BMenuField* menufield
+					= dynamic_cast<BMenuField*>(FindView("filemenu"));
+				if (menufield == NULL)
+					return;	
 				BMenu* menu = menufield->Menu();
 
 				// check audio file
@@ -267,7 +271,10 @@ HWindow::MessageReceived(BMessage* message)
 		case M_EVENT_CHANGED:
 		{
 			const char* path;
-			BMenuField* menufield = cast_as(FindView("filemenu"), BMenuField);
+			BMenuField* menufield
+				= dynamic_cast<BMenuField*>(FindView("filemenu"));
+			if (menufield == NULL)
+				return;
 			BMenu* menu = menufield->Menu();
 
 			if (message->FindString("path", &path) == B_OK) {
@@ -308,7 +315,9 @@ HWindow::MessageReceived(BMessage* message)
 void
 HWindow::SetupMenuField()
 {
-	BMenuField* menufield = cast_as(FindView("filemenu"), BMenuField);
+	BMenuField* menufield = dynamic_cast<BMenuField*>(FindView("filemenu"));
+	if (menufield == NULL)
+		return;
 	BMenu* menu = menufield->Menu();
 	int32 count = fEventList->CountRows();
 	for (int32 i = 0; i < count; i++) {
@@ -403,11 +412,11 @@ void
 HWindow::Pulse()
 {
 	HEventRow* row = (HEventRow*)fEventList->CurrentSelection();
-	BMenuField* menufield = cast_as(FindView("filemenu"), BMenuField);
-	BButton* button = cast_as(FindView("play"), BButton);
-	BButton* stop = cast_as(FindView("stop"), BButton);
+	BMenuField* menufield = dynamic_cast<BMenuField*>(FindView("filemenu"));
+	BButton* button = dynamic_cast<BButton*>(FindView("play"));
+	BButton* stop = dynamic_cast<BButton*>(FindView("stop"));
 
-	if (menufield == NULL)
+	if (menufield == NULL || button == NULL || stop == NULL)
 		return;
 
 	if (row != NULL) {