Is there a function like SUMIF for text values that concatenates rather than
sums?

I have a set of data as follows:

Truck No. Product Comments
----------- --------- ------------------
123 R-Gas Fully Reconciled
456 R-Gas Tank Dried
123 G-Gas Refilled

There are other columns of numbers. I then have a summary row for each truck
number using sumif for the number columns, but I need to concatenate the
comments in the summary row for say truck 123 to be:
"R-Gas"&":"&" Fully Reconciled"&", "&Char(10)&"R-Gas"&":"&" Refilled"
with the results in one text wrapped cell displayed as follows:
R-Gas: Fully Reconciled
R-Gas: Refilled

Thanks