diff --git a/application.py b/application.py
index 3f95473..dd4a629 100755
--- a/application.py
+++ b/application.py
@@ -231,23 +231,28 @@ class Application(object):
         return self.mini_buffer
     def mini_buffer_is_open(self):
         return self.mini_buffer is not None
-    def open_mini_buffer(self, prompt, callback, method=None, tabber=None,
-                         modename=None):
+    def open_mini_buffer(self, prompt, callback, method=None, tabber=None, modename=None):
         if self.mini_buffer_is_open():
             self.close_mini_buffer()
         self.mini_prompt = prompt
         self.mini_buffer = minibuffer.MiniBuffer(callback, method, tabber, modename)
-        window2.Window(self.mini_buffer, self, height=1, width=self.x-1-len(self.mini_prompt)-1)
-        self.mini_active = True
+        try:
+            window2.Window(self.mini_buffer, self, height=1,
+                           width=self.x-1-len(self.mini_prompt)-1)
+            self.mini_active = True
+        except minibuffer.MiniBufferError:
+            self.mini_buffer = None
+            self.mini_prompt = ''
     def exec_mini_buffer(self):
         self.mini_buffer.callback(self.mini_buffer.make_string())
         self.close_mini_buffer()
     def close_mini_buffer(self):
+        self.mini_active = False
         if self.mini_buffer_is_open():
             self.mini_buffer.close()
         self.mini_buffer = None
         self.mini_prompt = ""
-        self.mini_active = False
+        assert not self.mini_active
     def get_mini_buffer_prompt(self):
         return self.mini_prompt
     def set_mini_buffer_prompt(self, p):
diff --git a/method.py b/method.py
index c11db2a..1ea7cfd 100644
--- a/method.py
+++ b/method.py
@@ -171,11 +171,7 @@ class Replace(Method):
         a.last_replace_before = self.before = vargs['before']
         a.last_replace_after = self.after = vargs['after']
         self.old_window = w
-        a.open_mini_buffer('I-Replace: ',
-                           lambda x: None,
-                           self,
-                           None,
-                           'replace')
+        a.open_mini_buffer('I-Replace: ', lambda x: None, self, None, 'replace')
 
 # navigating between buffers
 class OpenFile(Method):
diff --git a/minibuffer.py b/minibuffer.py
index d066ca8..bd17949 100644
--- a/minibuffer.py
+++ b/minibuffer.py
@@ -1,5 +1,8 @@
 import buffer2
 
+class MiniBufferError(Exception):
+    pass
+
 # minibuffer is a singleton
 mini = None
 class MiniBuffer(buffer2.Buffer):
diff --git a/mode_python.py b/mode_python.py
index e85a912..33c0533 100644
--- a/mode_python.py
+++ b/mode_python.py
@@ -1,6 +1,6 @@
 import commands, os.path, sets, string, sys
 
-import color, completer, default, mode2, lex2, method, regex
+import color, completer, default, mode2, lex2, method, regex, tab2
 import ctag_python
 
 from point2 import Point
diff --git a/mode_replace.py b/mode_replace.py
index 20cc240..1a13a72 100644
--- a/mode_replace.py
+++ b/mode_replace.py
@@ -26,6 +26,9 @@ class Replace(mode2.Fundamental):
             self.add_action_and_bindings(action, sequences)
 
         _find_next(w, False)
+        if w.buffer.method.p1 is None:
+            w.application.set_error('%r was not found')
+            raise minibuffer.MiniBufferError
         _set_prompt(w.buffer.method, w.buffer.method.old_window)
 
     def name(self):
@@ -62,6 +65,9 @@ class CancelReplace(method.Method):
         w.application.set_error("Replace cancelled")
 
 def _set_prompt(m, w):
+    if m.p1 is None:
+        w.application.mini_prompt = '%r was not found' % m.before
+        return
     (x, y) = m.p1.xy()
     count = 0
     while y < len(w.buffer.lines):
@@ -128,3 +134,4 @@ def _end(w):
     w.application.clear_highlighted_ranges()
     w.buffer.method.old_cursor = None
     w.buffer.method.old_window = None
+    assert not w.application.mini_active