I cannot select only part of the text in an Edit Data cell.
pgadmin 1.10.0, GNOME Ubuntu 9.10, 64-bit:
(This does NOT occur in Windows pgadmin 1.10.0)
1. Open an Edit Data window.
2. Click in a cell.
3. Click again. All the text in the cell will be selected. (e.g. "abcdef")
4. Click again to set the insertion cursor.
5. Drag and select only part of the text (e.g. select "def" from "abcdef")
6. Press Ctrl-C or choose Edit->Copy
7. Paste the copied item somewhere else. It doesn't have to be in the Edit Data window. For instance, I pasted it into a gedit window.
8. The entire text will be pasted (e.g. "abcdef" above), not the substring you selected and copied.
Dan