MSP430 bootstrap loader help

Hi you all,
I'm relatively new to this list.
From time to time I browse through the newsgroup, and sometimes it happens to me
to get some valuable info.
But this is the first time I insert a post, and, not surprisingly, it is a
request of help.
I've developed the software for a target board with a TI MSP430F1611 MCU, that's
used for data acquisition, and that has already been deployed on field in a
certain number of units.
Originally, it was not required in-system re-programming, so (in the board
hardware layout) the two MCU pins necessary for the I/O to the ROM
factory-programmed bootstrap loader (BSL) were used for other functions, and
they were not made externally available.
Instead, on an externally accessible connector, are available the pins for a
serial RS232 line (connected by a trasceiver to the MCU internal USART).
Now we think it would be fine to add to the board in-system reprogrammability
(as always, we overlooked the frequency of unavoidable necessity of software
maintenance and extensions!).
It seems to me that the simplest solution should be the addition (on the highest
segments of flash memory) of a tweaked "clone" of the original BSL, with the
exactly identical functional interface, but operating with the two pins already
available on field for serial communications.
The bootstrap loader could be invoked by the application program at start, as a
response to a particular pre-defined startup sequence, or during normal
operation, on the reception of a convenient command through the same serial
channel.
It seems to me that such a solution would be very easy if it were available the
MSP430 bootstrap loader in source code format, because it will be sufficient to
modify th involved I/O pin references.
Do you know if the MSP430 BSL source code is somewhere available, and, possibly,
where?
In alternative, do you know about a similar software, availbale as source, at a
reasonable cost (possibly free)?
At last, can you suggest a convenient (and simple) different solution?
Thanks in advance. Andrea.

Thue wrote:
> I'm relatively new to this list.

I don't have an answer for your question, but if you ask it again
on the yahoo msp430 list, there are a lot of knowledgeable folk
there who will help.

Clifford Heath.