diff --git a/compressor/filters/base.py b/compressor/filters/base.py
index 2a6e444..e3a75e7 100644
--- a/compressor/filters/base.py
+++ b/compressor/filters/base.py
@@ -55,9 +55,9 @@ class CompilerFilter(FilterBase):
                     infile = tempfile.NamedTemporaryFile(mode='w')
                     infile.write(self.content)
                     infile.flush()
+                    self.options["infile"] = infile.name
                 else:
-                    infile = open(self.filename)
-                self.options["infile"] = infile.name
+                    self.options["infile"] = self.filename
             if "{outfile}" in self.command:
                 ext = ".%s" % self.type and self.type or ""
                 outfile = tempfile.NamedTemporaryFile(mode='w', suffix=ext)
@@ -65,7 +65,7 @@ class CompilerFilter(FilterBase):
             cmd = stringformat.FormattableString(self.command).format(**self.options)
             proc = subprocess.Popen(cmd_split(cmd),
                 stdout=self.stdout, stdin=self.stdin, stderr=self.stderr)
-            if infile is not None:
+            if infile is not None or self.filename is not None:
                 filtered, err = proc.communicate()
             else:
                 filtered, err = proc.communicate(self.content)
diff --git a/compressor/tests/precompiler.py b/compressor/tests/precompiler.py
new file mode 100644
index 0000000..6cc185a
--- /dev/null
+++ b/compressor/tests/precompiler.py
@@ -0,0 +1,19 @@
+#!/usr/bin/env python
+import optparse
+
+def main():
+    p = optparse.OptionParser()
+    options, arguments = p.parse_args()
+    
+    f = open(arguments[0])
+    content = f.read()
+    f.close()
+    
+    f = open(arguments[1], 'w')
+    f.write(content.replace('background:', 'color:'))
+    f.close()
+
+ 
+if __name__ == '__main__':
+    main()
+    
\ No newline at end of file
diff --git a/compressor/tests/tests.py b/compressor/tests/tests.py
index 9cd51a4..afa0eaa 100644
--- a/compressor/tests/tests.py
+++ b/compressor/tests/tests.py
@@ -481,3 +481,17 @@ CssTidyTestCase = skipIf(
     find_command(settings.COMPRESS_CSSTIDY_BINARY) is None,
     'CSStidy binary %r not found' % settings.COMPRESS_CSSTIDY_BINARY
 )(CssTidyTestCase)
+
+class PrecompilerTestCase(TestCase):
+    
+    def setUp(self):
+        self.command = 'python %s/precompiler.py {infile} {outfile}' % os.path.dirname(__file__)
+        self.filename = os.path.join(os.path.dirname(__file__), 'media/css/one.css')
+        f = open(self.filename, 'r')
+        self.content = f.read()
+        f.close()
+
+    def test_precompiler(self):
+        from compressor.filters.base import CompilerFilter
+        output = CompilerFilter(content=self.content, filename=self.filename, command=self.command).output()
+        self.assertEqual(u"body { color:#990; }", output)