diff --git a/scrapy/contrib/domainsch.py b/scrapy/contrib/domainsch.py
index 0755cf23d..c0ffbdcba 100644
--- a/scrapy/contrib/domainsch.py
+++ b/scrapy/contrib/domainsch.py
@@ -1,18 +1,19 @@
 """
-Domain Schedulers keep track of next domains to scrape. They must implement the
-following methods:
+The Domain Scheduler keeps track of next domains to scrape. They must implement
+the following methods:
 
 * next_domain()
   return next domain to scrape and remove it from pending queue
 
 * add_domain(domain)
-  add domain to pending domains to scrape
+  add domain to pending queue
 
 * remove_pending_domain(domain)
-  remove domain from pendings, do nothing if not pending
+  remove (all occurrences) of domain from pending queue, do nothing if not
+  pending
 
 * has_pending_domain(domain)
-  Return ``True`` if the domain is pending, ``False`` otherwise
+  Return ``True`` if the domain is pending to scrape, ``False`` otherwise
 
 """
 
@@ -30,7 +31,7 @@ class FifoDomainScheduler(object):
         self.pending_domains.append(domain)
 
     def remove_pending_domain(self, domain):
-        self.pending_domains.remove(domain)
+        self.pending_domains = [d for d in self.pending_domains if d != domain]
 
     def has_pending_domain(self, domain):
         return domain in self.pending_domains