159 chars with symbols results in a msg:41:NACK/0x00000001/Message Length is invalid

Currently seeing a strange bug in build from SVN (Build `Dec 20 2012 12:06:01'). When a message is sent that is 159 chars and has symbols in - such as:

aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa£5.00/£4.00aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

I get a fail

2013-02-25 16:41:08 FAILED Send SMS [SMSC:default] [SVC:Kannel] [ACT:] [BINF:] [FID:] [META:?smpp?ChannelId=REMOVED] [from:me] [to:+44123456789] [flags:-1:0:-1:-1:3] [msg:161:aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa..5.00/..4.00aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa] [udh:0:]

Add 2 more chars to it and try again - goes through no problems...

My guess is it's calculating the pound signs as 2 chars (or maybe the backslash?) then trying to concatenate and then failing on the length when converting to GSM to send to the SMSC? Or am I way off with that? can anyone else recreate this fail on their setup, using latest from SVN?

Config for the smsc is:

group = smsc
smsc = smpp
smsc-id = defaultSMSC
smsc-admin-id = defaultSMSC
host = address.removed
port = 1775
receive-port = 1775
smsc-username = blah
smsc-password = blah
system-type = ""
address-range = ""
# allow messages to UK mobile numbers only allowed-prefix = 07;+447;

# Optional Parameters

group = smpp-tlv
name = CampaignId
tag = 0x1400
type = octetstring
length = 32
smsc-id = defaultSMSC

group = smpp-tlv
name = Reference
tag = 0x1401
type = octetstring
length = 32
smsc-id = defaultSMSC

group = smpp-tlv
name = ChannelId
tag = 0x1402
type = octetstring
length = 32
smsc-id = Oxygen8

# End of Optional Parameters