diff --git a/frappe/app.py b/frappe/app.py
index 2dc6c2fec0..09013cd7f4 100644
--- a/frappe/app.py
+++ b/frappe/app.py
@@ -5,6 +5,7 @@ from __future__ import unicode_literals
 import sys, os
 import json
 import logging
+import MySQLdb
 
 from werkzeug.wrappers import Request, Response
 from werkzeug.local import LocalManager
@@ -70,6 +71,14 @@ def application(request):
 	except Exception, e:
 		http_status_code = getattr(e, "http_status_code", 500)
 
+		if (http_status_code==500
+			and isinstance(e, MySQLdb.OperationalError)
+			and e.args[0] in (1205, 1213)):
+				# 1205 = lock wait timeout
+				# 1213 = deadlock
+				# code 409 represents conflict
+				http_status_code = 409
+
 		if frappe.local.is_ajax:
 			response = frappe.utils.response.report_error(http_status_code)
 		else:
diff --git a/frappe/desk/form/meta.py b/frappe/desk/form/meta.py
index c9808451d6..9bfca60494 100644
--- a/frappe/desk/form/meta.py
+++ b/frappe/desk/form/meta.py
@@ -68,6 +68,7 @@ class FormMeta(Meta):
 			self.set("__listview_template", get_html_format(listview_template))
 
 		self.add_code_via_hook("doctype_js", "__js")
+		self.add_code_via_hook("doctype_list_js", "__list_js")
 		self.add_custom_script()
 
 	def _add_code(self, path, fieldname):
diff --git a/frappe/model/rename_doc.py b/frappe/model/rename_doc.py
index 0792d59270..44e9d19308 100644
--- a/frappe/model/rename_doc.py
+++ b/frappe/model/rename_doc.py
@@ -84,7 +84,9 @@ def rename_parent_and_child(doctype, old, new, meta):
 	update_child_docs(old, new, meta)
 
 def validate_rename(doctype, new, meta, merge, force, ignore_permissions):
-	exists = frappe.db.get_value(doctype, new)
+	# using for update so that it gets locked and someone else cannot edit it while this rename is going on!
+	exists = frappe.db.sql("select name from `tab{doctype}` where name=%s for update".format(doctype=doctype), new)
+	exists = exists[0][0] if exists else None
 
 	if merge and not exists:
 		frappe.msgprint(_("{0} {1} does not exist, select a new target to merge").format(doctype, new), raise_exception=1)
diff --git a/frappe/public/js/frappe/misc/number_format.js b/frappe/public/js/frappe/misc/number_format.js
index 5e344fa9c7..35d093c46b 100644
--- a/frappe/public/js/frappe/misc/number_format.js
+++ b/frappe/public/js/frappe/misc/number_format.js
@@ -178,7 +178,7 @@ function _round(num, precision) {
     var m = Math.pow(10, d);
     var n = +(d ? num * m : num).toFixed(8); // Avoid rounding errors
     var i = Math.floor(n), f = n - i;
-    var r = (f == 0.5) ? ((i % 2 == 0) ? i : i + 1) : Math.round(n);
+    var r = (!precision && f == 0.5) ? ((i % 2 == 0) ? i : i + 1) : Math.round(n);
     return d ? r / m : r;
 }
 
diff --git a/frappe/public/js/frappe/request.js b/frappe/public/js/frappe/request.js
index 1753763652..00b0e0a546 100644
--- a/frappe/public/js/frappe/request.js
+++ b/frappe/public/js/frappe/request.js
@@ -68,6 +68,9 @@ frappe.request.call = function(opts) {
 
 			msgprint(__("Not permitted"));
 		},
+		409: function(xhr) {
+			msgprint(__("Another transaction is blocking this one. Please try again in a few seconds."));
+		},
 		417: function(data, xhr) {
 			if(typeof data === "string") data = JSON.parse(data);
 			opts.error_callback && opts.error_callback(data, xhr.responseText);
diff --git a/frappe/utils/data.py b/frappe/utils/data.py
index 08707b33e0..dd0db4cd87 100644
--- a/frappe/utils/data.py
+++ b/frappe/utils/data.py
@@ -210,12 +210,14 @@ def flt(s, precision=None):
 	"""Convert to float (ignore commas)"""
 	if isinstance(s, basestring):
 		s = s.replace(',','')
+
 	try:
 		num = float(s)
 		if precision is not None:
 			num = rounded(num, precision)
 	except Exception:
 		num = 0
+
 	return num
 
 def cint(s):
@@ -235,7 +237,7 @@ def cstr(s):
 		return unicode(s)
 
 def rounded(num, precision=0):
-	"""round method for round halfs to nearest even algorithm"""
+	"""round method for round halfs to nearest even algorithm aka banker's rounding - compatible with python3"""
 	precision = cint(precision)
 	multiplier = 10 ** precision
 
@@ -245,7 +247,7 @@ def rounded(num, precision=0):
 	floor = math.floor(num)
 	decimal_part = num - floor
 
-	if decimal_part == 0.5:
+	if not precision and decimal_part == 0.5:
 		num = floor if (floor % 2 == 0) else floor + 1
 	else:
 		num = round(num)