empty result on SELECT with LIKE on '...Z%'

I have a table with name of people.
In this table there is 'MENDEZ PATRICIA'
If I try SELECT * FROM people WHERE nom LIKE 'MEND%'
result => MENDEZ PATRICIA
If I try SELECT * FROM people WHERE nom LIKE 'MENDEZ%'
result => empty  (here is the problem)
If I try SELECT * FROM people WHERE nom LIKE 'MENDEZ P%'
result => MENDEZ PATRICIA

Thank for this beautiful database.

thil