From d30d7b2188063a157967feb81cfea8915a79ea6e Mon Sep 17 00:00:00 2001
From: ThomasV <thomasv@gitorious>
Date: Sat, 12 Apr 2014 19:53:52 +0200
Subject: [PATCH] fix #651

---
 lib/transaction.py |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/lib/transaction.py b/lib/transaction.py
index 3ee0c11..7f1044e 100644
--- a/lib/transaction.py
+++ b/lib/transaction.py
@@ -428,8 +428,11 @@ class Transaction:
             s += txin['prevout_hash'].decode('hex')[::-1].encode('hex')   # prev hash
             s += int_to_hex(txin['prevout_n'],4)                          # prev index
 
-            if for_sig is None:
-                signatures = txin['signatures']
+            signatures = txin.get('signatures', {})
+            if for_sig is None and not signatures:
+                script = ''
+
+            elif for_sig is None:
                 pubkeys = txin['pubkeys']
                 sig_list = ''
                 for pubkey in pubkeys:
@@ -455,7 +458,7 @@ class Transaction:
                 else:
                     script = txin['scriptPubKey']                    # scriptsig
             else:
-                script=''
+                script = ''
             s += var_int( len(script)/2 )                            # script length
             s += script
             s += "ffffffff"                                          # sequence
-- 
1.7.1