mysql 4.0(freebsd) 升级到5.0+(linux)的出现的问题

mysql> desc cdb_attachments;
l)y3y:G4LDX9j#[0+-------------+-----------------------+------+-----+---------+----------------+木铎校园 BBS 社区,P&U a
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| Field       | Type                  | Null | Key | Default | Extra          |木铎校园 BBS 社区 \M;X
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+-------------+-----------------------+------+-----+---------+----------------+木铎校园 BBS 社区aVP+BYi7}
| aid         | mediumint(8) unsigned | NO   | PRI | NULL    | auto_increment |木铎校园 BBS 社区_,Y%^p3L z
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| tid         | mediumint(8) unsigned | NO   | MUL | 0       |                |
,]~,r;w3r,?6i0| pid         | int(10) unsigned      | NO   | MUL | 0       |                |
O)W r}:w+S tb0| dateline    | int(10) unsigned      | NO   |     | 0       |                |木铎校园 BBS 社区cI8}efh
| readperm    | tinyint(3) unsigned   | NO   |     | 0       |                |木铎校园 BBS 社区rV Uz6u
| price       | smallint(6) unsigned  | NO   |     | 0       |                |木铎校园 BBS 社区f9gwR"c
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| filename    | char(50)              | NO   |     | NULL    |                |
[ ^`9sKr+Xl0| description | char(50)              | NO   |     | NULL    |                |
#_Lj;`3F/L+OO0| filetype    | char(25)              | NO   |     | NULL    |                |
QBX;^7tin j0| filesize    | int(10) unsigned      | NO   |     | 0       |                |
n,W#]hA+h0| attachment  | char(50)              | NO   |     | NULL    |                |
/vnp%Q x;c0| downloads   | mediumint(8)          | NO   |     | 0       |                |木铎校园 BBS 社区-t0a/kk~ f
| isimage     | tinyint(1) unsigned   | NO   |     | 0       |                |
F8TT)I!I9v&T0| uid         | mediumint(8) unsigned | NO   | MUL | 0       |                |
#P3|9R-?b"` U?0| thumb       | tinyint(1) unsigned   | NO   |     | 0       |                |
lR4C`,e0| remote      | tinyint(1) unsigned   | NO   |     | 0       |                |木铎校园 BBS 社区9Q-{h4x3g
+-------------+-----------------------+------+-----+---------+----------------+木铎校园 BBS 社区 O M2[u`
16 rows in set (0.01 sec)
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N;yM6d0木铎校园 BBS 社区YoB?p4qj*u4rJ

8W-[w~&p&D0mysql> desc cdb_attachments;
7S+x?Nl;k G0+-------------+-----------------------+------+-----+---------+----------------+
$AM(t@_T.Ki0| Field       | Type                  | Null | Key | Default | Extra          |木铎校园 BBS 社区f$C!Y7@8aE$U
+-------------+-----------------------+------+-----+---------+----------------+
$rtGKo0| aid         | mediumint(8) unsigned |      | PRI | NULL    | auto_increment |木铎校园 BBS 社区'lNi(z
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| tid         | mediumint(8) unsigned |      | MUL | 0       |                |木铎校园 BBS 社区%w;JSUF1~Tv*R
| pid         | int(10) unsigned      |      | MUL | 0       |                |
7k g3\ Usk0| dateline    | int(10) unsigned      |      |     | 0       |                |木铎校园 BBS 社区DE#]g
vN.n
| readperm    | tinyint(3) unsigned   |      |     | 0       |                |木铎校园 BBS 社区5|+NU'm1Ep:\u]uc|
| price       | smallint(6) unsigned  |      |     | 0       |                |
1pzY]v1Y5f w0| filename    | char(100)             |      |     |         |                |
4w!G!^S @1c!i0| description | char(100)             |      |     |         |                |木铎校园 BBS 社区l[;|`8y8T/c
| filetype    | char(50)              |      |     |         |                |木铎校园 BBS 社区AgC `&Tlhu+`
| filesize    | int(10) unsigned      |      |     | 0       |                |
1p4\nl$c#`_%CF_7G0| attachment  | char(100)             |      |     |         |                |木铎校园 BBS 社区oqw5wBiluE6w
| downloads   | mediumint(8)          |      |     | 0       |                |
lv j\`M1N ~$AO&uv/o0| isimage     | tinyint(1) unsigned   |      |     | 0       |                |木铎校园 BBS 社区&S7N Ki0Pj!PF&y
V/[
| uid         | mediumint(8) unsigned |      | MUL | 0       |                |
v;z[q`/P0| thumb       | tinyint(1) unsigned   |      |     | 0       |                |木铎校园 BBS 社区 z(eq x#or ^x
| remote      | tinyint(1) unsigned   |      |     | 0       |                |
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B)LPO/r;K0+-------------+-----------------------+------+-----+---------+----------------+木铎校园 BBS 社区0I#wb3G7x~'L
16 rows in set (0.00 sec)木铎校园 BBS 社区Qr'b)C`%BqG

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P-vh0上面的是freebsd上mysql4.0+的表结构，将表文件直接copy到linux下，启用mysql5.0+,表结构如下面的表。。。
r.AjJB0W0木铎校园 BBS 社区!O4t/o?,Q"a)|_6s

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