Glenn says: 'It's very difficult to sign quality players but my standards are very high and I repeat that I only want to bring in players who will improve the team.
'I think that by bringing in David James people can hopefully see where I'm coming from.
'He will be a major influence for us next season. When was the last time West Ham signed a current international with his best years in front of him?'
James was handed the yellow No.1 jersey, formerly worn by Shaka Hislop, before taking part in his first day's training at Chadwell Heath earlier today.
Glenn continues: 'David is the first piece in a jigsaw that I might not be able to put together instantly and, while I have funds available, I certainly don't have the funds the big four have got. So I've got to try and spend it as carefully and as wisely as I can.
'If I have to wait a little bit longer, then I'll wait, because ultimately patience will pay off.
'Even if I have to wait until after the start of the season, then I'll continue to be patient until I get the right men in.
'I hope I've made a statement of intent by trying to get David James to West Ham. Now that we've managed to attract him to our club, hopefully my other targets will see that and it will hopefully make my job a little bit easier if I reach the stage where I get the opportuniity to talk to those players.'