I think that the T4 and the T5 are the same camera. I made a brief comment on my T5 in this thread and all I would add is that I was annoyed by the shutter lag.
Philip Greenspun, used to praise it morning noon and night ~8 years ago at photo.net
So much that I felt I must get my hands on one. I never did.
The T4 was discontinued long before digicams killed film P&S, patent infringment claims other companies had against Yashica on this model (think it had something to to with the waist level finder and the T4 super).