I refer to the posts regarding glide slope warnings from the EGPWS.
Glide slope warnings do not necessarily mean the aircraft was doing anything dangerous ie below the glide slope (unless the said aircraft was attempting to fly an ILS in IMC). Two scenarios spring to mind, first with the crew becoming visual with PAPI's and them being set to a slightly different angle to the glide slop (glide slopes will tend bring an aircraft in 'higher' than PAPI's). Thus an aircraft can be descending below glide slope indications (normally after DA) as the PAPI path is folllowed. Once the 2/3rd 'dot' threshold is reached one will get a 'Glide Slope' warning. I admit, not very common but does happen. Most occurances at dual military/civil airports where fast jets are based and PAPI's can be set as low as 2.5 degrees.
Second scenario, when conducting visual approaches it is always a good plan to back up the approach with all available nav aids. If performing a visual approach to a runway with no approach aids, it is sometimes possible to use the recipricle runways ILS backcourse to give guidance. This is not an approved method as it is illegal to fly back course approaches under JAR however it can aid in situational awareness. Having the ILS for the other runway tuned can give 'Glide Slope' warnings also.
Sorry, bit off the topic of the thread but I do find it interesting that any post about FR always attracts comments from peolpe who will make safety judgements with little facts.
And as a note to a previous post, I have not heard of an FR aircraft running off the end of a Runway. Please elaborate.