UID	Class	Range	Purpose
Protected Range	0	0x00000000 - 0x0FFFFFFF	Development use only
	1	0x10000000 - 0x1FFFFFFF	Legacy UID allocations
	2	0x20000000 - 0x2FFFFFFF	V9 protected UID allocations
	3	0x30000000 - 0x3FFFFFFF	Reserved
	4	0x40000000 - 0x4FFFFFFF	Reserved
	5	0x50000000 - 0x5FFFFFFF	Reserved
	6	0x60000000 - 0x6FFFFFFF	Reserved
	7	0x70000000 - 0x7FFFFFFF	Vendor IDs.
Unprotected Range	8	0x80000000 - 0x8FFFFFFF	Reserved
	9	0x90000000 - 0x9FFFFFFF	Reserved
	A	0xA0000000 - 0xAFFFFFFF	V9 unprotected UID allocations
	B	0xB0000000 - 0xBFFFFFFF	Reserved
	C	0xC0000000 - 0xCFFFFFFF	Reserved
	D	0xD0000000 - 0xDFFFFFFF	Reserved
	E	0xE0000000 - 0xEFFFFFFF	Development use only
	F	0xF0000000 - 0xFFFFFFFF	Legacy UID compatibility range

如果开发一些Symbian的项目，将来要签名的使用Protected UID，程序必须签名才能安装在真机上。Unprotected可以用来做一些测试、教学程序。

    每个应用程序都有3个UID。uid1用于表示Symbian OS平台程序的类型：For EXE uid1 = 0x1000007A；  For DLL&APP uid1 = 0x10000079；For ECom Plugin 0x10009D8D。UID2一般都去固定值0x100039CE，我也没有弄清楚具体的作用。UID3标识应用程序。SID的取值和UID3一样。VID一般都取默认的0。UID都在程序的MMP中定义。