diff --git a/pisi/api.py b/pisi/api.py
index 30ac32f7..39be35b6 100644
--- a/pisi/api.py
+++ b/pisi/api.py
@@ -584,11 +584,7 @@ def prepare_for_build(pspecfile, authInfo=None):
         ctx.ui.error(_("Unsatisfied Build Dependencies:"))
         for dep in dep_unsatis:
             ctx.ui.warning(dep.package)
-
-    # FIXME: Don't exit for now! It's annoying to test on a system that
-    # doesn't has all packages made with pisi.
-    # Will be enabled on the full-pisi system.
-    #        sys.exit(1)
+        # FIXME: raise an exception if ignore-depends not given
 
     return pb
 
diff --git a/pisi/build.py b/pisi/build.py
index d2fa59c9..f26dc50a 100644
--- a/pisi/build.py
+++ b/pisi/build.py
@@ -220,11 +220,9 @@ class PisiBuild:
             buf = open(scriptfile).read()
             exec compile(buf, "error", "exec") in localSymbols, globalSymbols
         except IOError, e:
-            ctx.ui.error(_("Unable to read Action Script (%s): %s") %(scriptfile,e))
-            sys.exit(1)
+            raise Error(_("Unable to read Action Script (%s): %s") %(scriptfile,e))
         except SyntaxError, e:
-            ctx.ui.error (_("SyntaxError in Action Script (%s): %s") %(scriptfile,e))
-            sys.exit(1)
+            raise Error(_("SyntaxError in Action Script (%s): %s") %(scriptfile,e))
 
         self.actionLocals = localSymbols
         self.actionGlobals = globalSymbols
diff --git a/pisi/cli/commands.py b/pisi/cli/commands.py
index 46db7c79..71748eea 100644
--- a/pisi/cli/commands.py
+++ b/pisi/cli/commands.py
@@ -22,6 +22,11 @@ import pisi.cli
 import pisi.context as ctx
 from pisi.uri import URI
 
+
+class Error(pisi.Error):
+    pass
+
+
 class Command(object):
     """generic help string for any command"""
 
@@ -45,8 +50,7 @@ class Command(object):
             return Command.cmd_dict[cmd]()
     
         if fail:
-            ctx.ui.info(_("Unrecognized command: ") + cmd)
-            sys.exit(1)
+            raise Error(_("Unrecognized command: ") + cmd)
         else:
             return None
     get_command = staticmethod(get_command)
@@ -102,7 +106,7 @@ class Command(object):
             dir = str(self.options.destdir)
             import os.path
             if not os.path.exists(dir):
-                raise Exception, _('Destination directory %s does not exist') % dir
+                raise Error, _('Destination directory %s does not exist') % dir
             self.options.destdir = os.path.realpath(dir)
 
 
@@ -160,7 +164,8 @@ class Command(object):
 
     def die(self):
         """exit program"""
-        ctx.ui.error(_('Program terminated abnormally.'))
+        #FIXME: not called from anywhere?
+        ctx.ui.error(_('Command terminated abnormally.'))
         sys.exit(-1)
 
 
@@ -170,11 +175,11 @@ class autocommand(type):
         Command.cmd.append(cls)
         name = getattr(cls, 'name', None)
         if name is None:
-            raise pisi.cli.Error(_('command lacks name'))
+            raise pisi.cli.Error(_('Command lacks name'))
         longname, shortname = name
         def add_cmd(cmd):
             if Command.cmd_dict.has_key(cmd):
-                raise pisi.cli.Error(_('duplicate command %s') % cmd)
+                raise pisi.cli.Error(_('Duplicate command %s') % cmd)
             else:
                 Command.cmd_dict[cmd] = cls
         add_cmd(longname)
diff --git a/pisi/lockeddbshelve.py b/pisi/lockeddbshelve.py
index 8d8bd306..2c82c632 100644
--- a/pisi/lockeddbshelve.py
+++ b/pisi/lockeddbshelve.py
@@ -57,9 +57,7 @@ class LockedDBShelf(shelve.DBShelf):
         try:
             fcntl.flock(self.lockfile, fcntl.LOCK_EX | fcntl.LOCK_NB)
         except IOError:
-            import sys
-            pisi.context.ui.error(_("Another instance of PISI is running. Try later!"))
-            sys.exit(1)
+            raise Error(_("Another instance of PISI is running. Try later!"))
         return self.db.open(filename, dbname, filetype, flags, mode)
 
     def close(self):
diff --git a/pisi/packagedb.py b/pisi/packagedb.py
index d43097f5..6d2e28e3 100644
--- a/pisi/packagedb.py
+++ b/pisi/packagedb.py
@@ -45,9 +45,7 @@ class PackageDB(object):
         try:
             fcntl.flock(self.lockfile, fcntl.LOCK_EX | fcntl.LOCK_NB)
         except IOError, e:
-             import sys
-             ctx.ui.error("PackageDB: %s" % e)
-             sys.exit(1)
+             raise Error(_("Cannot lock PackageDB: %s") % e)
         self.d = shelve.open(self.fname)
         self.dr = shelve.open(self.fname2)