I tried to edit my boards.txt settings for the Arduino UNO, changed the baud rate to 57600. Then I got an error with the FTDI adapter and my Arduino UNO (tried with both of them). However. I just burned an UNO optiboot bootloader into one one of my 328p's, after some confusion, since one had the duemilanove bootloader, and the other one had UNO bootloader.
I tried to upload the info-sketch to the ATMega328p with UNO bootloader with the FTDI adapter, but got an error saying that the programmer is not responding (with both 57600 and 115200 upload baud rate).
So I put the 328p with Uno-loader in the original UNO, uploaded the info-sketch, hit "i", and got the info.
I also put the same 328p into my breadboard with the FTDI, and hit "i" again, and got the info.
RESULT FOR UNO:
Arduino ShowInfo
Show what the Arduino has to tell you.
Menu
0 = System LED off
1 = System LED on
2 = i2c_scanner
i = Show information
h = Show menu
r = Test serial communication
s = Speed tests
t = Timer Register Dump
? = Show menu
Type command, followed by Enter
Information
sketch Size = 26208 (80%)
free RAM = 1618
RAM used = 686 (30%)
VERSION = 4.3.2
DATE = Sep 27 2012
TIME = 18:22:07
AVR_LIBC_VERSION_STRING = 1.6.4
FILE = /var/folders/9k/m717t9pj29gf8l9b012xdb500000gn/T/build5842348411495699102.tmp/sketch_sep27a.cpp
STDC = 1
OSCCAL = 158
GPIOR0 = 0x0
GPIOR1 = 0x0
GPIOR1 = 0x0
RAMEND = 0x8FF
XRAMEND = 0x8FF
E2END = 0x3FF
FLASHEND = 0x7FFF
LOW FUSE = 0xFF
HIGH FUSE = 0xDE
EXTENDED FUSE = 0xFD
LOCK BITS = 0xCF
Processor according to compiler = AVR_ATmega328P
SIGRD : not defined (let's make it 5 and see what happens).
Signature = 0x1E, 0x95, 0xF
calibration = 15
Number of seconds since start = 4
Internal Temperature = 23.8 Celsius (the offset could be wrong).
RESULT FOR FTDI:
Arduino ShowInfo
Show what the Arduino has to tell you.
Menu
0 = System LED off
1 = System LED on
2 = i2c_scanner
i = Show information
h = Show menu
r = Test serial communication
s = Speed tests
t = Timer Register Dump
? = Show menu
Type command, followed by Enter