See Ask Orange from the Orange web site <http://www.orange.net.au/>

What is a split SMS?
When an Orange mobile customer receives an SMS message of greater
than 120 characters, the message will be split into two SMS messages
and delivered to the customers’ handset. The messages will be numbered
to indicate the first and second half of the message. This ensures
that Orange mobile customers will receive the full SMS message sent to
them by mobile users from other mobile carriers.

Why does Orange split incoming SMS?
The Orange mobile network delivers 120 character SMS messages at a
time. Other mobile networks in Australia work on 160 character SMS
messages. As a result, Orange has implemented a solution to ensure
that Orange Mobile customers will not loose the end of received SMS
messages.

Will I be charged for split SMS?
No. There is no additional charge when receiving additional messages
for a split SMS.

Will the service still apply while national roaming?
Yes.

Will PrePay services receive split SMS messages?
Yes

How do I read a split message?
Split SMS messages will be numbered to indicate the first and second
half of a message. The first half of the message will be numbered (1
of 2) and the second half (2 of 2). To read a message:
i) select the message that starts with [1of2]
ii) scroll through the first message and read as per normal
iii) open the second message [2of2], scroll through and read

Can I now send an SMS message greater than 120 characters?
No. Message splitting applies to inbound SMS messages being sent to an
Orange Mobile customer. Orange mobile customers can send a 120
character SMS message.

How many characters of the incoming message will appear in the first
half of the split SMS message?
Approximately the first 110 characters of an incoming message will
appear in the first half of a split SMS message. The remaining
characters will be taken up by [1 of 2] and the three dots at the end
of the first half of the message. The messages that exceed 120
characters will be "cut" at the end of a word rather than part way
through where the 120 character limit is reached part way through a
word. For example, a message ending with the words "See you
tomorrow….." may have reached the 120 character limit at the O in you.
In this case, the first message will end with "See…" and the second
message will start with "…you tomorrow".  

I've used Orange from it launched its own CDMA network. They are as
good (or bad) as the rest of them. You certainly can't go past their
rates.

In general CDMA of either Telstra or Orange variety is usually not as strong
indoors. This is because the networks are scarcely populated at the moment,
and thus geographical coverage is the most important point. Over time, with
high user density, new bases will be placed in areas which have an effect of
better inbuilding coverage.

If you work or live in a high rise, check the coverage before buying,
preferably on an actual handset.

Occasionally happens on CDMA when the phone doesnt respond to the page quick
enough. Happens even in a good coverage area.
Telstra have this problem licked with software upgrades, dont know about
Orange