Index: trunk/src/crosshair.c
===================================================================
--- trunk/src/crosshair.c	(revision 29325)
+++ trunk/src/crosshair.c	(revision 29326)
@@ -1055,6 +1055,17 @@
 	PCB->hidlib.grid = save_grid;
 }
 
+static void pcb_crosshair_tool_logics(pcb_hidlib_t *hidlib, void *user_data, int argc, pcb_event_arg_t argv[])
+{
+	int *ok = argv[1].d.p;
+	int id = argv[2].d.i;
+	pcb_board_t *pcb = (pcb_board_t *)hidlib;
+	if (pcb->RatDraw && !pcb_tool_get(id)->allow_when_drawing_ratlines) {
+		pcb_message(PCB_MSG_WARNING, "That tool can not be used on the rat layer!\n");
+		*ok = 0;
+	}
+}
+
 /* allocate GC only when the GUI is already up and running */
 static void pcb_crosshair_gui_init(pcb_hidlib_t *hidlib, void *user_data, int argc, pcb_event_arg_t argv[])
 {
@@ -1066,7 +1077,6 @@
 	pcb_hid_set_line_width(pcb_crosshair.GC, 1);
 }
 
-
 /* ---------------------------------------------------------------------------
  * initializes crosshair stuff
  * clears the struct
@@ -1087,6 +1097,7 @@
 	pcb_crosshair.tool_arc = pcb_crosshair.tool_poly = pcb_crosshair.tool_poly_hole = -1;
 
 	pcb_event_bind(PCB_EVENT_GUI_INIT, pcb_crosshair_gui_init, NULL, crosshair_cookie);
+	pcb_event_bind(PCB_EVENT_TOOL_SELECT_PRE, pcb_crosshair_tool_logics, NULL, crosshair_cookie);
 }
 
 
Index: trunk/src/librnd/core/event.c
===================================================================
--- trunk/src/librnd/core/event.c	(revision 29325)
+++ trunk/src/librnd/core/event.c	(revision 29326)
@@ -41,6 +41,7 @@
 	"pcbev_load_pre",
 	"pcbev_load_post",
 	"pcbeb_new_tool",
+	"pcbeb_tool_select_pre",
 	"pcbev_board_changed",
 	"pcbev_board_meta_changed",
 	"pcbev_board_fn_changed",
Index: trunk/src/librnd/core/event.h
===================================================================
--- trunk/src/librnd/core/event.h	(revision 29325)
+++ trunk/src/librnd/core/event.h	(revision 29326)
@@ -40,6 +40,7 @@
 	PCB_EVENT_LOAD_POST,              /* called after loading a new design, whether it was successful or not */
 
 	PCB_EVENT_TOOL_REG,               /* called after a new tool has been registered; arg is (pcb_tool_t *) of the new tool */
+	PCB_EVENT_TOOL_SELECT_PRE,        /* called before a tool is selected; arg is (int *ok, int toolid); if ok is non-zero if the selection is accepted */
 
 	PCB_EVENT_BOARD_CHANGED,          /* called after the board being edited got _replaced_ (used to be the PCBChanged action) */
 	PCB_EVENT_BOARD_META_CHANGED,     /* called if the metadata of the board has changed */
Index: trunk/src/tool.c
===================================================================
--- trunk/src/tool.c	(revision 29325)
+++ trunk/src/tool.c	(revision 29326)
@@ -143,6 +143,7 @@
 	pcb_board_t *pcb = (pcb_board_t *)hidlib;
 	char id_s[32];
 	static pcb_bool recursing = pcb_false;
+	int ok = 1;
 	
 	if ((id < 0) || (id > vtp0_len(&pcb_tools)))
 		return -1;
@@ -153,13 +154,14 @@
 	 */
 	if (recursing)
 		return -1;
+
+	/* check if the UI logic allows picking that tool */
+	pcb_event(hidlib, PCB_EVENT_TOOL_SELECT_PRE, "pi", &ok, id);
+	if (ok == 0)
+		id = pcbhl_conf.editor.mode;
+
 	recursing = pcb_true;
-	
-	if (pcb->RatDraw && !pcb_tool_get(id)->allow_when_drawing_ratlines) {
-		pcb_message(PCB_MSG_WARNING, "That mode is NOT allowed when drawing ratlines!\n");
-		id = PCB_MODE_ARROW;
-	}
-	
+
 	pcb_tool_prev_id = pcbhl_conf.editor.mode;
 	pcb_tool_next_id = id;
 	uninit_current_tool();