diff --git a/Lib/cookielib.py b/Lib/cookielib.py
index f260bc5..f2df467 100644
--- a/Lib/cookielib.py
+++ b/Lib/cookielib.py
@@ -464,26 +464,42 @@
     for ns_header in ns_headers:
         pairs = []
         version_set = False
-        for ii, param in enumerate(re.split(r";\s*", ns_header)):
-            param = param.rstrip()
-            if param == "": continue
-            if "=" not in param:
-                k, v = param, None
-            else:
-                k, v = re.split(r"\s*=\s*", param, 1)
-                k = k.lstrip()
+
+        # XXX: The following does not strictly adhere to RFCs in that empty
+        # names and values are legal (the former will only appear once and will
+        # be overwritten if multiple occurrences are present). This is
+        # mostly to deal with backwards compatibility.
+        for ii, param in enumerate(ns_header.split(';')):
+            param = param.strip()
+
+            key, sep, val = param.partition('=')
+            key = key.strip()
+
+            if not key:
+                if ii == 0:
+                    break
+                else:
+                    continue
+
+            # allow for a distinction between present and empty and missing
+            # altogether
+            val = val.strip() if sep else None
+
             if ii != 0:
-                lc = k.lower()
+                lc = key.lower()
                 if lc in known_attrs:
-                    k = lc
-                if k == "version":
+                    key = lc
+
+                if key == "version":
                     # This is an RFC 2109 cookie.
-                    v = _strip_quotes(v)
+                    if val is not None:
+                        val = _strip_quotes(val)
                     version_set = True
-                if k == "expires":
+                elif key == "expires":
                     # convert expires date to seconds since epoch
-                    v = http2time(_strip_quotes(v))  # None if invalid
-            pairs.append((k, v))
+                    if val is not None:
+                        val = http2time(_strip_quotes(val))  # None if invalid
+            pairs.append((key, val))
 
         if pairs:
             if not version_set: