diff --git a/pressure-vessel-test-ui b/pressure-vessel-test-ui
index 31bc7ba37a31d7c5962db1850dbc4a24a069023a..ded3e12cee88f7e81627f365e63067bdbb0a31ac 100755
--- a/pressure-vessel-test-ui
+++ b/pressure-vessel-test-ui
@@ -135,6 +135,7 @@ class Gui:
         self.shell_combo.append(
             '--shell-instead', 'Instead of running the command')
         self.shell_combo.set_active(0)
+        self.shell_combo.connect('changed', self._shell_changed)
         self.grid.attach(self.shell_combo, 1, row, 1, 1)
 
         row += 1
@@ -157,6 +158,13 @@ class Gui:
 
         row += 1
 
+    def _shell_changed(self, shell_combo):
+        if shell_combo.get_active_id():
+            self.xterm_check.set_active(True)
+            self.xterm_check.set_sensitive(False)
+        else:
+            self.xterm_check.set_sensitive(True)
+
     def _describe_runtime(
         self,
         path        # type: str