I keep getting error on this book

Instant result on Asp.net 2.0 instant result on online diary
this is DayView.aspx.vb

mDiaryEntry = New DiaryEntry(CInt(Session("DiaryId")), CDate(dayShownLabel.Text))

Is anybody know how to recorrect this problem?
my error message is

Conversion from string "13 8¿ù 2007" to type 'Date' is not valid.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.InvalidCastException: Conversion from string "13 8¿ù 2007" to type 'Date' is not valid.



Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Line 19: mDiaryEntry = New DiaryEntry(CInt(Session("DiaryId")), CDate(dayShownLabel.Text))
Line 20: changeDayCalendar.SelectedDate = CDate(dayShownLabel.Text)
Line 21: changeDayCalendar.VisibleDate = changeDayCalendar.SelectedDate

Are you using different culture than degault en-us. If you are using en-us, check that there are some special characters in "13 8¿ù 2007". That's why it is unable to cast this string into Date. If you are using different culture than en-us, then problem can be something else.

Gaurav